Yandex

There are too many:

• perfect offices
• great conditions for working, very comfortable working places, rooms, negotiation rooms, kitchens, and all
• great atmosphere; everyone wants to create an excellent product; no one works only for money
• great projects and perfect experience
• very clever and skilled co-workers
• premiums and food compensations, free parking

Nobody likes to document and write comments in code. There are no requirements to do this, no general code style, and no requirements to write tests, etc. So this totally depends on the project and its team lead. The incoming barrier for a new-comer is pretty high as the code is not documented at all.

Another issue is too many unsuitable functional approaches for coding in Java that often result in bad-readable code.