Because I get here and ...... I got nothin'.
The brain does a sudden release and all I get is "poof" nothing. This is more commonly known as a "brain fart."
OR, more often than not, I get here and find myself having to type one handed beecause the little demands I bounce/hold/feed/soothe/change her. (note the latter stops me all together.) This slows down the creative flow and 9 out of 10 times, brings my thoughts to a grinding halt.
Either way, I got nothin'.