...is that they are sensitive to overbrewing, and get bitter.

Unfortunately, one of the attributes of many not-very-good teas is that they are bitter, whether you overbrew them or not.

I drink a lot of tea--at least four teabags worth a day.

I have the attention span of a gnat.

Work is an interrupt-driven environment, which means even if I set an alarm, there's a high likelihood I cannot get to the tea to stop it steeping until far too late.

The upshot of all the above facts in aggregate is that I can sometimes get all the way through a $20 tin of teabags, over the course of several months, and never know whether or not I like the tea.