They say, if there is enough space for a cockroach to insert its whiskers into, then that space is enough for the entire cockroach to get into that space. Actually the cockroach calculates the space it needs that way.

Similarly, for most of the men, if their tummy can get into a space then they can fit into or get through that space.

As a corollary: For most men, their tummies make an entrance and then they do.
As a lesson: Reduce tummy.