...mostly because they simply don't do anything wrong. 
...or at least I know, they know better.Then there's the really wonderful sandwich technique I've picked up in the States. It's really wise in every way, because why would you offer advice to somebody you wouldn't wish to stay motivated and proceed? Unless your advice was for them not to proceed, hahaha!
Sandwich goes:
Top: Find what's good, even if it's but a good tendency or a good reason, but something that confirms the good in all of it.
Middle: Then mention what you've noticed as a problem with some potential suggestion
Bottom: Back to why it's all worth it and what good things to expect.
It sounds like a cold formula and something it does get ridiculous when people use it, but know not why or what for. They use it to protect themselves. But if you are full of heart and care, then you will figure out that this method is to help you show your heart and your care in a way that has a useful and elevating effect.
I sometimes forget to use it, too...
...it's because I take it for granted and think that I always regard it, but sometimes people cannot know what I don't speak out. I might've thought: Wow, here's a real diamond in the rough - or - I can't wait what becomes of this one. But I did not write it, because it would've felt awkward. Meh...
or inverted butterbread 
), in any case, it tastes better than eating one stale bread! 
All, enough about gastronomy, I want to say that to criticize something one would be good to attach the praise of something else, so that the artist does not develop a one-sided attitude. Maybe I'm very kind, but I've never heard a track in OSC that doesn't have something good in it (outside of OSC, I hear it very often!).
... Don't get sick! 
