About T-Shirt Design
The joke on I Should Be In Time Out Shirt is easy to understand, and that is a big part of why it works. Fans of everyday humor will probably get the joke first, but it is simple enough for almost anyone to understand.
You could wear it for holidays, bring it out for birthdays, or just keep it in the normal shirt rotation. It has the easy look of a graphic tee that lets the saying do most of the talking. It is simple, funny, and easy to picture on someone who likes this kind of humor.