I did this too, back when I had to use public terminals and obviously could not use password managers. But the idiosyncrasies of password rules on many sites ad

I did this too, back when I had to use public terminals and obviously could not use password managers. But the idiosyncrasies of password rules on many sites added to the complexity of my own "transformation" of the base password, until the whole thing while workable, became burdensome. These days I do all logging in on my own PC and therefore I see no real need not to use a password manager and unique, random passwords for each site. The obvious downside to this approach is if I were ever to be caught in a situation where I MUST log in to some site but do not have access to my PC AND phone, and therefore cannot risk opening the password DB on an alien system. Pretty unlikely scenario though.