Tracking isn't working again. Nothing is happening.

Hi @Paul_Gringo:

This is a Mask for an Effect that you're trying to have track something in your footage, right?

One thing to double-check is that the Effect is enabled when you do the tracking.

Sometimes, though, what we're trying to track in a shot isn't something Premiere can track well.  

I usually try tracking in Premiere Pro first and for faces that tends to work really well.  For anything else, I frequently replace the Clip with an After Effects Composition and do a Mask Track or Roto Brush there.  If that doesn't work so well, then I switch to Mocha AE.  If that doesn't work so well, I usually hand the shot of to someone who specializes in Silhouette for roto work.

This all said, have you had a chance to try the new Select Object feature in the Premiere Pro beta?  It's pretty impressive.  You can have the beta installed along side the release version (currently 25.x) and the prior version (24.x).