How to handle natural stone slabs for a terrace?

If there are no joints at all, then from my layman's perspective that is already botched. The gravel provides the base for the slabs. Through rain and small movements, the gravel in the joints shifts, so that it has to be regularly refilled in the first weeks.

My neighbor told me that in his company they only lay patio slabs on gravel with a written exclusion of follow-up work in case of settling. Because according to him, these occur almost always, sometimes earlier, sometimes later.