Here's why your iPhone doesn't always show the accept and decline buttons when receiving calls
The question has plagued iPhone owners for years: Why can't I always decline an incoming call?
Often the only obvious option given is "slide to answer" - leaving someone trying to avoid a call no choice but to watch their phone ring until voicemail picks up. Those who have spotted the "decline" button wonder why it isn't always there.
The answer is deceptively straightforward. If your iPhone screen is locked, the slide-to-answer bar appears. But if your screen is unlocked and open, the decline and answer buttons will show.
When your phone is locked, here's what an incoming call looks like:
If your screen is unlocked when the call comes in, this is what you'll see:
The elusive decline button really bums some people out: