Why are there no earthworms in my soil?

I've noticed in a number of areas on my property that there are little to no earth worms.  A few of these places are garden beds I've worked for years on adding mulch and organic material to.  Obviously I'm missing something or there is something in the soil that is driving them away?

What we have done in the past is to go to a fishing store and purchase red wigglers.

Also building soil health will help keep the earthworms from going somewhere where there is more to eat.

I highly recommend Dr. Bryant Redhawks soil series:

https://permies.com/wiki/redhawk-soil

You or others might find this interesting:

https://permies.com/t/54687/adding-worms-soil

Thank you, I'll go through those links as I have time, it does look pretty thorough.