Note, that some albums among this list, might produced Top 40, or even Top 20 singles, but the albums themselves sold poorly, or just poorly compared with their earlier releases.
(In alphabetical order)
1) Astra by Asia (1985)
Enjoying huge success with their self-titled debut (especially in the US), and the follow-up Alpha, Astra wasn't as successful as its predecessors. Still they continued their "tradition" by releasing albums starting and ending with the letter "A" (a tradition they kept till Silent Nations). Well to be honest I believe it was weaker than their first two albums, yet not rubbish. Since then Asia wasn't on the spotlight anymore, still their follow-ups had moderate success in Japan.
2) Caught In The Game by Survivor (1983)
Despite the nice cover art, this album didn't go well unlike it's predecessor, Eye Of The Tiger. In my opinion this one sounded better, richer and louder, than Eye Of The Tiger. My guess why it flopped, it would be because people were expecting another Eye Of The Tiger, and once they found out they won't have what they wanted, it flopped. Thankfully they found a replacement (Jimi Jamison) once Dave Bickler departed, and Survivor got back on their feet with Vital Signs. Otherwise Survivor would pass in history as an one-hit wonder band. Anyway, even if Caught In The Game didn't have any significant chart success back in the day, this album is highly appreciated among AOR fans.
3) Chicago XIV by Chicago (1980)
It's one of those albums you might not get why they sold poorly. Actually their previous release, Chicago XIII, sold poorly as well compared with their successful releases from the 70s, but this one was even worse. Guess the reason was problems with their then label (Columbia Records) and lack of promotion. Thankfully they got back on their feet with Chicago XVI featuring the power ballad Hard To Say I'm Sorry, which put them back on the spotlight. Still Chicago XIV is perhaps their most overlooked album among their whole discography.
4) Door To Door by The Cars (1987)
After the tremendous success of Heartbeat City, The Cars took a small hiatus by focusing on solo projects (Ric Ocasek released This Side Of Paradise and Benjamin Orr released The Lace, featuring the hit single Emotion In Motion (peaking at #15) and Stay The Night (peaking at #24) respectively. Door To Door is considered their worst album by many, and it was the album that put an end on their career for more than two decades. I disagree though because personally I find it better than many albums released during that year. Perhaps if they released Double Trouble as a single it might do better I believe.
5) Dream Come True by A Flock Of Seagulls (1986)
Having a successful self-titled debut and a successful follow-up (Listen) as well, since The Story Of A Young Heart, AFOS popularity started to fade away. This one sold even more poorly than their 3rd album, and it didn't even made it on the charts, neither in the UK nor in the US. The lack of this album's success lead AFOS to a break-up. Although they reunited, and they're still active, they never managed to recapture the success they had during the years1982-1983.
6) Flash Gordon by Queen (1980)
Although it's a Soundtrack album essentially, it's considered a Queen's album. It was the Soundtrack for the movie Flash Gordon which received many awards, although the album didn't have the same luck. Perhaps the reason was, it was different from regular Queen's stuff so it wasn't embraced as much. In fact it's pretty weird as an album because there are not many tracks that are actually songs, but it's a compilation of sound effects more or less. This doesn't mean it's bad though. They got back on the track with Hot Space though (at least in their homeland) , but since The Game, their popularity in the US started to fade.
7) Heart Like Sky by Spandau Ballet (1989)
In my opinion, this is one of the worst albums of the 80s if not THE worst. If I was a member of Spandau Ballet, I'd definitely disown this one. There are no memorable songs there, and if Through The Barricades was dull compared with their earlier works, this one makes Through The Barricades sounding awesome. Well, no wonder why this album was so bad and it failed success. Band members' relationships weren't great by the time, and teamwork is essential for a band.
8. Inside Information by Foreigner (1987)
Although it reached Platinum status, and featuring two Top 10 hits as well, it sold more poorly than all previous band's releases. It was a bad sign for the band and it was their last album that produced any hits. Since then, Foreigner's popularity declined dramatically. Perhaps it was Lou Gramm's lack of interest towards the band by the time, focusing more on his solo career. Still I believe it's as good as their previous releases, and it has nothing to be jealous about.
9) Life As We Know It by REO Speedwagon (1987)
Although 2 Top 20 singles came out from this album (That Ain't Love and In My Dreams peaking at #16 and #19 respectively), this album sold poorly compared with their 3 previous releases (Hi-Infidelity, Good Trouble, Wheels Are Turnin') reaching only Gold status. Whilst Gold status generally isn't bad, it meant that REO Speedwagon started to drift away from the spotlight. Since then, they never managed to recapture the success they had with Hi-Infidelity. Not even the success with Good Trouble. But anyway, this album wasn't lesser than their big ones I believe.
10) The Doctor by Cheap Trick (1986)
Cheap Trick managed to receive huge success during late 70s and early 80s both in the US and in Japan as well. But since original bassist's (Tom Petersson) departure, their commercial success started to fade away. Among their mid-80s albums, The Doctor was the one that was their biggest commercial failure. It was a change on the band's sound as well featuring a more AORish sound. It wasn't as bad as it was described, but this is just my opinion. Cheap Trick made a comeback with their next album,The Lap Of Luxury, but as it happened with many 70s and 80s bands, their popularity declined dramatically during the 90s.
11) The Warmer Side Of Cool by Wang Chung (1989)
Wang Chung, were one of the most successful Synth-Pop bands in the mid-80s in the US. Well, despite the fact being British themselves, they were more popular in the US. Their Mosaic album sold well (it went Gold), considering they were a Singles band mostly (this doesn't mean their non-single songs were inferior.) . But their follow up, The Warmer Side Of Cool didn't. Perhaps the reason was, by the time Synth-Pop's popularity started to decline, and like many others among their peers, stopped being on the spotlight, in both sides of the Atlantic.
12) Turn back by Toto (1981)
I don't know why this one flopped, but I believe it was perhaps the bad cover art. Too childish in my opinion. But apart from the bad cover art, I don't see anything wrong with the songs here. I'd say it is an overlooked Melodic Rock classic. Although this album flopped in US, it reached #3 in Japanese charts. Their next album Toto IV (featuring their biggest hit, Africa) saved their career in fact. Although their follow-up releases never managed to be as successful as Toto IV.
13) Two Hearts by Men At Work (1985)
It's not a surprise this one flopped. The main reason wasn't the record itself. Whilst it's not as strong as their two previous albums, it's still decent. But the reason was, Men At Work members' relationships weren't in a good state. Also by the time the album was recorded, only 2 out of 5 members (Colin Hay & Greg Ham particularly) of the original line-up were part of it. So essentially it wasn't a Men At Work album, but a Colin Hay & Greg Ham duo album. After the release of this album they called it quits.
14) U-Vox by Ultravox (1986)
Ultravox were very popular during the first half of the 80s, in the UK and in Europe as well. But here despite the fact the album reached the Top 10 in the UK charts, it didn't produce any Top 20 Hit Singles, and it was a change in musical direction as well, leaning towards more into a Mainstream Pop sound, unlike their previous Synth-Pop albums, which probably was a disappointment, among the band's fans. After the release of this album, Ultravox broke up, but reunited during the 90s (Billy Currie, was the only member among the original line-up by then) releasing two albums, which sold poorly. Later in late 00s, they reunited once again, with all members from Midge Ure era line-up being present.
15) Vulture Culture by Alan Parsons Project (1984)
Alan Parsons Project were much more appreciated in the US and Germany (especially in Germany) than in their homeland, UK. Although this album reached #1 in Germany and it sold well, it was the album when US market started to turn their backs on them, and it was the album where Alan Parsons Project career took a "U" turn. Their two follow-up releases sold even more poorly, so APP were disbanded as a result. My guess, why this album flopped would be, because it was more poppish compared with their earlier releases, and it was something the fans didn't expect.