There's no such thing as an "easy-to-remember password", because people have so many passwords. Do you think your site's password is the only one your customers

There's no such thing as an "easy-to-remember password", because people have so many passwords. Do you think your site's password is the only one your customers need to remember? Most people with any kind of online life will have so many logins that memorizing even the more important ones (in their opinion, not yours) is out of the question, no matter how the individual passwords are chosen or generated. (I just checked my own password vault, and I have about 80 of them. This is probably fairly typical for anyone who spends a lot of time on the internet.) "Forbid users from choosing their own passwords" is functionally equivalent to "require users to write down their passwords".