I don't pick up unknown numbers, I call them back a bit later. If the number turns out to belong to a call center, great, I just hang up. If it's a real person,

I don't pick up unknown numbers, I call them back a bit later. If the number turns out to belong to a call center, great, I just hang up. If it's a real person, sure, let's chat. If somebody really wants something, they'll call again. Also, sending an SMS to the unknown number and asking for a name works wonders. If someone really wants something they will take the time to type.