Thread:ARTaylor/@comment-27710776-20181026214553/@comment-122823-20181027013421

In the comics, Hulk and Thing continue fighting for whatever reason despite whatever resolution they came to after their last bout. Fighting again is probably a reference to that. As far as in-universe, Hulk is never presented as particularly intelligent and often makes decisions in the heat of the moment. He probably wasn't thinking clearly when he hit Thing.