Catalyst monitor is never ready for smog test: could it be due to some other failure such as:

Maintenance/Repairs
1

a bad catalyst converter?

2

or Catalyst monitor has been disabled??

3

or a bad Catalyst monitor ???

4

If you have a code post it here, along with what car, miles, and age.

5

Your oxygen sensor and oxygen sensor heater monitors must have run and passed before the catalytic converter monitor will run.
Have they all run to completion and passed?

6

If you don’t have a code, most parts stores will read them for you for free.