This is why your iPhone has different caller options

Scenario one

You're on your iPhone, tapping about like a happy plumber. You get a phone call. Your iPhone presents you with two immediate options: Decline or Accept

So far, so underwhelming. But that's before Scenario two slaps you in the chops:

You get a phone call. Your iPhone presents you with one immediate option...

This subtle variation in answering options has left many of us bemused - squealing at our inconsistent handsets with the confused rage of a dad attempting to set up a VCR recording.

Turns out we're not alone either, with Business Insider scratching their heads over the same conundrum.

It transpires the difference in caller options is dictated by whether your phone is unlocked (scenario one) or locked (scenario two).

Why, you ask? If your phone is rattling about in your pocket, a swipe gesture makes it much harder to answer by accident. You can still reject it by simply hitting the lock button on your phone again. 

So there we go. Case closed.