If you're a user or developer that actively reports bugs or enhancements requests to Apple via their Bug Reporter system (also known as Radar), you most probably know already that not all bugs unveiled this way are equal in the eyes of the Cupertino company.
The reasons Apple's developers sometimes refuse to fix some of the reported bugs are unknown and this happens often enough as reported by numerous users of the Apple Radar system on the web.
For instance, one possible reply you could get from Apple's developers is "We are closing this bug since our engineers are aware of the issue and will continue to track it," which might be short for saying "we know about it, but we won't fix it."
Performing a quick Google search for the phrase above on Tim Burks' Open Radar database of bugs reported to Apple, for example, will get some results with both closed and still open issues.
Ill-mannered bug reporters don't have a lot of success when dealing with Apple
To make it even clearer that Apple is not shying away from ignoring user-submitted bugs, yesterday a developer working for Google had an intense conversation via Twitter with one of Apple's developers about his bug reports being overlooked.
The conclusion was that given a large number of issues reported, Apple devs will sometimes take into account the way a user formulates the issue description. According to Apple's Benjamin Poulain: "Say you have 100 bugs, you have time to fix 10. The bugs from nice reporters are much more likely to be picked."
The fact that Apple does not give any sign of acknowledgement to some of the bugs reported is a well-known fact in the development community, and this Twitter conversation could provide a possible reason why it happens.
As a conclusion, sweet talking Apple into acknowledging your bug report should make it a lot more probable to be noticed and fixed.
@awfulben @xeenon can you confirm, or retract, your statement that Apple engineers ignore bugs based on a personal grudge against me?
— Jake Archibald (@jaffathecake) September 10, 2015
There's been a suggestion that Apple engineers ignore particular iOS bugs because they have a grudge against me… from an Apple engineer.
— Jake Archibald (@jaffathecake) September 10, 2015
@jaffathecake @xeenon Say you have 100 bugs, you have time to fix 10. The bugs from nice reporters are much more likely to be picked.
— Benjamin Poulain (@awfulben) September 10, 2015
@awfulben so do/don't you (& others?) ignore particular bugs because of a grudge against me? If so, which bugs are blocked in this?
— Jake Archibald (@jaffathecake) September 11, 2015
@jaffathecake You have many colleagues who are waaaayyy nicer and open to discussions. When they report bugs, they are often looked quickly.
— Benjamin Poulain (@awfulben) September 11, 2015
Update: Clarified the difference between Apple's Radar bug reporting system and Open Radar.