Bees travel so far away from their "home" beehives that they seem to get lost and never return. I've seen them travel 70 or more blocks away. Once they hit about 50 blocks distant, they don't seem to be able to find their way back. I've seen bees at night 30-40 blocks from their beehive, just flying around. But they seem unable to find their way home. If I lead them near their hives with flowers, then they enter them right away (it's night, after all). Otherwise, it's hit or miss whether they return (usually they don't).

I spawned 10 bees near three (empty) hives to test this theory. They all found the hives soon after locating flowers and gorging themselves. But, with one night/day cycle, all but three were gone forever. The following game day, they were all gone except one.

This problem seemed to start happening either at 21w23a or 1.17-pre1, and has continued through pre2 and pre3.