Can't AirDrop from iPhone to Mac (but can from Mac to iPhone)

You know what I realized last night? The AirDrop from the iPhone and iPad to my Mac actually is working. It’s just that much of the time the delivery is taking such a long time I thought it wasn’t. Like instead of seconds, it was taking minutes. But if I leave the AirDrop screen open it was working.

What could cause the Mac to be so slow about receiving AirDrop data to the point it seems it’s not working, and even becomes useless for copy/paste between devices?