What is the most "Thankless" job?

Oh man, I worked at a call center for a little over four years doing internet technical support... Never again.

I am thankful for those that can push through it (especially on the more direct customer service side of things), as I certainly don't have the cognitive fortitude for it.

One of my roles at my current job still involves a lot of support, but at least its not over the phones thankfully.

I did that once. Now I try to get them to laugh on the phone, ya know? Make their day a little better without disrupting their average handle time stats.