De-escalator

Anyone else had a comp plan where your commission drops after hitting quota?

I always assumed your percent goes up once you hit quota, but recently received an offer with 15% commission until you hit quota, then 7.5% after quota.

Trying to understand why it would make sense for a business to do this: I always figured escalators are because you’ve covered your base/expenses once you hit quota, so they are basically making pure profit and encourage you to keep going.

Has anyone had this structure and can explain what is behind it?

Edit: This is for a SaaS role. I can’t imagine situation where they are concerned about selling contracts they are unable to fulfill.