I use a formula I came up with for generating my passwords, so it is a real pain when I find a website that insists my password has to be up to 8 characters, all lower case letters. (Yes, I still find ones like this).
Another thing I find annoying are sites that insist you change your password every so many months. Why??/ I created a unique password just for this site and now I have to change it even though my account has never been breached? Talk about an insecure website. When people have been using a password for a while, it is memorized. When you force them to now use a new password, what is the best way for most people to remember it. In my experience, I found a lot of people tend to write it on a sticky note and keep it near their computer. Personally, I use an encrypted password manager, but not everyone is as computer savy.