Yup, banks are one of the largest problems. On of my banks forces a 4-digit, number only password, that needs to be rotated every 90 days, with no consecutive

Yup, banks are one of the largest problems. On of my banks forces a 4-digit, number only password, that needs to be rotated every 90 days, with no consecutive numbers, can't repeat all passwords, no numbers repeated, and a few other conditions. Heck, even random generated numbers will fail to get accepted sometimes (1671 has two ones. 1894 has two consecutive numbers. etc). It starts to get really hard to pick new ones as time goes by and you've already used up lots of memorable patterns.