As my list gets longer and longer lifers occur in two main ways:
1. Targetted trips looking for particularly species (particularly on longer trips).
2. When a vagrant turns up and hangs around long enough for me to get to see it.
Sometimes both happen on the same trip (Isabelline Wheatear turned up just as we happened to be staying at Kingfisher Park about 30km away).
I don't see you eating a talking bird
Fat Mike - NOFX