Why Birds...?

Continuing the thread ,
What makes me tick after completing 30 years of birding this week?
(Recorded date 12 Nov. 1978).
Was it on the Nevern est. recently, marvelling at 3 juvenile Whoopers arriving looking bewildered & lost as they entered a new chapter in their short life so far, now without parents!
Or was it a couple of weeks previous, after an exhilarating trek through some fierce Madagascar rain forest, finding the "mythical rarity" in the form of a female Bernier's Vanga.
Or tomorrow, trying to catch Oystercatchers, to help unravel their strategies for wintering in South Wales.
So is it seeing new birds? seeing new birds in new places? or the more scientific study of birds that makes me tick??
I don't know... but every day it happens..