"incompetence in development field"
It is your incompetence to recognize what bugs the Graphene team is accountable for and what bugs come from Google and others and the team has to work with that. And the bugs reported to the Graphene team are quickly eliminated. You are looking in the wrong places blaming the wrong persons.
Considering how big Google is and how small the GOS team, and what the programmers earn... And the people come along and point their fingers in the wrong direction.