Your tools are probably dying because you don't maintain them regularly, or correctly, after use.
If you think about it, drawing brake fluid through the tool, then leaving it sit in there for a year, is the same thing as not bleeding/flushing the fluid through your brake system, which causes all that mud and crap in the bottom of your master cylinder housing etc.
Another thing that damages them, is not removing all the crap out of the master cylinder housing with a children's aspirator before you start using the tool. Doing this just jams all that crap into the tool.
The tool is a simple check valve with a spring and a bearing.
You'll find if you draw some MMO through the check valve when your finished using it, before you put it away, the brake fluid will not clog them up.
I also draw some fresh DOT 4 fluid through it before I use it again.
Its a tool, keep it clean and take care of it, and they never wear out etc.
I have about a dozen new boxes in my tool box draw that I've never had to open, since I started doing this several years ago.