@Peter - security is a compromise. If your password is very hard to remember then it's also very hard for a hacker/bot to guess.

The compromise is in how usable the security measure is vs how much business value you put on your website/data.

This will differ depending on what you use your website for.

If it's a blog for a hobby, then it may be an irritant if your site gets hacked but if you are a sole trader with an eCommerce site who's living depends on it, then security is whole different ball game.

Not just in the site being compromised but in customer trust and brand identity too.

Have a look at some password services such as LastPass for storing and encrypting your passwords for use on multiple devices.