I cannot hear the cab sim in my physical cabinet - why?

When you use a Torpedo equipped with cabinet simulation (Captor X, Captor, Live, Studio, C.A.B. M) and your amp with a cabinet, you will not hear the Torpedo cab sim in your cabinet.

For Torpedo Captor, Captor X, Live , Studio:

The amp is connected to the load box. The SPEAKER OUTPUT is connected too to the load box. When you connect a cabinet to the SPEAKER OUTPUT you are receiving the amp signal, which in the case of the Captor and Captor X, can be attenuated.

The signal coming from the amp is taken from the load box to then feed all the Torpedo processing to send this signal out of the DI and Line outputs (XLR or Jack). This derived signal is not linked at any time to the SPEAKER OUTPUT. It cannot be sent to the speaker outputs.
You can only hear the cab sim and all the attached effects and parameters using the Line outputs (XLR or Jack) through your audio interface/monitors/PA.

For Torpedo C.A.B M

The SPEAKER OUT is directly linked to the AMP/INST/LINE IN . The signal coming out of the SPEAKER OUT is exactly the signal coming in the pedal, unaffacted. The signal does not go through any of the Torpedo processing.

To hear the cab sim and other audio treatments applied by the Torpedo C.A.B M, you need to use the DI, line or headphone outputs.