in my opinion the right outfit is really important! I know looks aren't everything but first impressions do count! for me, the perfect outfit is one that makes me feel good. I looks good and suits my bodyshape and its occassion appropriate. I make sure that even if it looks great, I have to feel comfortable. there's nothing worse than having to check or re-adjust your outfit constantly when you're supposed to be having fun!
The perfect outfit definitely doesn't depend on the price or label. Its all about how it makes me feel :)
For me the "right outfit" is the one that makes me feel confident. Even if I am wearing something trendy or if I get loads of compliments if I don't feel good or if I constantly have to make adjustments or check myself in a mirror the outfit is not right (sorry that sentence is terrible but I think you can get the point). For me its all about how I feel not about the cost, colors or style of what I'm wearing.