I do Free File Fillable Forms, and I’m something of an amateur tax expert - friends and family come to me for advice. But yet every year there’s some weird edge case that I have to figure out by digging through the Schedule D instructions or the 1040 instructions or… Sometimes I’ll go through one of the paid systems up until the submission step where you have to pay, to make sure that my numbers line up.

The system is just really complicated if you have anything weird, and “anything weird” happens a lot.