The main issue with this kind of method (using an algorithm to create a password) is that it makes it very hard to change your password if needed.

E.g, let 's say you use your algorithm for your passwords : Amazon get AnxPv4rz, HN get hsxPv4rz, etc... Now, someone get your password for Amazon one way or another (social engineering, poorly protected website, etc...). You have two choices :

* Change your algorithm for all your passwords. Depending on the number of different websites you use, it will probably be a very heavy process, and you might forget some websites.

* Use a different algorithm for Amazon. If you start going this way, you'll quickly find yourself with 5-6 different algorithm, each more or less complicated. That's pretty much why people use Password managers : they want secure passwords, without having to remember each and every one of them because it gets complicated after the 5th. And if you use a password manager, you might as well use completely random passwords.