Why T-shaped people?

A T-shaped person is capable in many things and expert in, at least, one.

As opposed to an expert in one thing (I-shaped) or a “jack of all trades, master of none” generalist, a “t-shaped person” is an expert in at least one thing but also somewhat capable in many other things. Alternate phrases for “t-shaped” include, “multi-skilled”, “generalizing specialist”, “icicle-shaped”, and “paint drip”.

I-shaped vs generalist vs T-shaped