The key to not break them is to not yank the sh*t out of them like a jackass. Not saying you are a jackass lol, but certain technique is needed.
With any pull starter, (with the easy ones this is more forgiving but they still execute same principle) you have to feel when the piston is top center (resistance in the pull starter reaches its peak and suddenly starts freeing itself) and then give it a quick solid pull.
Also if you don't do it properly the engine cam back fire and definitely break the pull starter.
After about 60 tanks in my cheapo baja Im still using the pull starter it came with, so I guess I’m doing it ok.
If the engine is well primed it should start with just 1 or 2 pulls.
And remember, no engine is made to need 20 pulls for starting.
The entire point being that you can just get the same replacement or a better quality one to easily swap it if you get the hang of it since replacing pull starters and NOT changing the technique will result in… more pull starte