Long answer, I happened to teach at undergraduate level during my days ad grad school (not really a T.A. but a sort of associate professor position that in the US is normally filled by PosDocs). At the time it seemed like a great idea and I was proud to "not having a single day of unemployment in my record".

The problem was when I decided to go back to work in industry instead of pursuing an academic career. Most employers would see me not as a fresh graduate from a prestigious graduate program, but as "just a teacher" trying to "switch careers".

It took 4 and a half months of eroded expectations, biter exchanges with H.R. folks and learning the ropes of the hiring game to find someone to actually give me a chance to prove myself in a support position that required no advanced degree and minimal technical skills (basically: speaks English, knows ksh and SQL). Then came the appalling realization that after 9 years of post K12 education I was apparently not qualified to answer the phone properly.

Of course, your mileage may vary. Much of my experience not necessarily comes from being in grad school, but from lack of soft skills and the ability to manage perception of potential employers.