We were assessed a too-low property tax one year (it was a carryover from the previous homeowner) I knew they’d come calling for it eventually and I didn’t want to take a cash hit years later. I tried – repeatedly – to get them to fix it and eventually gave up. About four years later, they hit me up for it, demanding interest and penalties. I had kept sufficiently good records I was able to waive those, but it was a big PITA. I understand why folks would give up, even if they knew the problem, as the government is just as bad correcting an error, regardless of the direction.