It is not a complicated invention.

The technical challenge is not particularly great.

But it solves a real problem, and the fact that it solves a real problem is what makes it an invention worth having.

The bathroom tissue holder patent is similar in character.

The problem it addresses — running out of toilet paper without a readily accessible spare — is one that virtually everyone has experienced.

The standard solution is to keep extra rolls somewhere in the bathroom: on the back of the toilet, in a cabinet, on a freestanding rack.