I stay answering calls. You just never know what it's about. I used to duck calls a lot until one day my boy called 4 times from a next number, answered the 5th time, turns out he had a very lucky day. Won 10000 on a scratch card and a further 870 on roulette at paddy power.
He knew I was not working and pretty broke and down in the dumps. Man set me up nicely.
Another time I was thinking of fucking the call but answered, turned out to be Informa PLC internal recruitment, head hunted me, even though I was working at the time the role and salary was just too good to pass by. Was hired after one face to face, started the following Monday.
And lastly, when my brother passed and my mum kept calling, I was in college but on break, couldn't hear my phone and took ages to reply because I thought she probably wants to tell me to pick up a few bits on the way home. Boy was I wrong when I returned the call.
Answer your calls folks, you literally never know. If it's nonsense then just cut the call short or say you don't have time and will call back.