Oh dear god.
I think Instagram has made this a lot worse. Whilst it can be used correctly, I've seen some complete lack of knowledge with regards to Depth of Field, and trying to recreate Bokeh, that's created some images that some might go 'oh it looks fine' but anyone who knows anything will go 'that's not right...'. That said, they think it looks lovely.
Personally, I'm quite new to photography. I'm currently building up a portfolio of photos, and having a 6D, I'm sure plenty would say that for someone so new, I better know how to use it. The thing is, I'm learning as fast as I can, and I've got very high standards for myself. So out of a typical shoot, my keep rate tends to be really low. That's not because any of the photos are particularly 'bad', I'd say 90-95% are in focus with correct exposure etc... It's just that as something that may one day represent me in a portfolio, I want them to be absolutely fantastic.
kd