Tim+ formulated the question :
I have *never* drained the fuel from my B&S lawnmower at the end of the
season and it has always started in the spring with a couple of extra
pulls. Been doing this for at least 20 years now.

Same here with my B&S powered lawn tractor. I ran it for the first time
a couple of weeks ago to cut grass, then again yesterday. Started at
the first attempt, as I have come to expect.