I don't know if there is a trend about that, but I think one big problem is that most games are released way too soon.
Most of the very first builds aren't polished enough.
A lot of devs are not paying attention to details and they don't realize to what extent it can become very harmful for their project.
Things like :
- Not adding music
- Not adding sound
- Not working on the UI
- Not proofreading the script
- Not play-testing the game before the public release
Are problematic, but they're often only the tip of the iceberg.
Many developers only have a short term vision of their project, hoping that visuals alone will do all the work.