Some people aren't as helpful as other users, focusing more on answering the fun questions instead of the ones looking for serious advice. There are certain users that answer in detail while others leave one or two sentences as well. For example, @dangerDoge has such a high MHO percentage because his responses are in-depth and cover all possible answers (or as best as he can think of). He also doesn't run around answering a ton of questions just to answer them.
A variety of reasons - Firstly the major hitters tend to get stuck into questions about issues people are having, if you give a thoughtful long response your chances of getting MHO are higher - If you give a lot opinions it can be tough say you give a 100 in a day and 60 are awarded MHOs. You would need 12 MHOs to keep on track for a 20% MHO percentage - It is not that bad to have a low MHO percentage but it can tell people what type of user you are - Lastly yes some people can be not MHO friendly for whatever reason blunt, trolling maybe even a bit mean/negative.
because this site is not just about giving advice. A big part of the questions are just for fun, and many people here are just to have fun, kill boredom or meet new people and not to give great advice on every question. Also, there can only be 2 MHO per question, means not everyone can have high MHO percentage.
I could easily boost my MHO percentage, but I don't care about it and I'm not here for that
I stopped giving good advice years ago when I stopped giving a shit. I've seen the same questions ad nauseum and can't be bothered to think about every question critically. This isn't school. For those questions that I give semi-decent advice, my answer usually gets drown out in the crowd. Now that I think about it, for the amount of trolling and condescending answers I give, I'm surprised my percentage isn't lower.
If the AVERAGE question has, say, 10 responses from each sex, then, the AVERAGE MHO percentage is going to be 1% (= 1 out of 10).
If the average question has 20 responses, then, the average MHO percentage will be 5% (= 1 out of 20).
In fact, the boy-responses for THIS question, RIGHT NOW, are a pretty good illustration... Right now there are 12 boy responses. If there were 12 responses to EVERY question, the average MHO would be 100/12 = 8.33%. And there are... 6 boys over 8.33% 5 boys under 8.33% 1 anon ... Yep. So, right now, this question is an almost perfect illustration of exactly how this works. (:
A lot of questions are just nonsensical and fun. The people with high percentages tend to avoid answering those. Also the people with the highest rates are typically very old users and a while ago they changed the system and just awarded a whole bunch of mho to those people even though the asker didn't choose them. So it's a bit skewed.