Door Checks?

[supplyguy]

Installed one new and one used but nearly new door check in my car when painted. The new one originally kept the door a good half inch from creasing the fender, then a quarter inch, and now I am back to tenderly opening the door because it's a millimeter from making contact (sorry for going back to metric). The door check is less than four months old. How can a door check go bad?

[So Cal Mark]

they usually break, but they can loosen up and let the door open too far