why is one ubuntu 22.04 usb stick mount-point /media/user/writable while another stick mounts at /media/user/<UUID> (some 128-bit hex)

Question

I have two flash drives with identical partitioning (according to parted print), each with only one ext4 partition. Inserting them one at a time (i.e. not using both at the same time), one mounts at /media/user/writable (good!) but the other at /media/user/5a654226-1856-4a9e-b7ab-c064a9cdecb0 .

In parted, the partitions have empty names - I tried naming, which made no difference. I want to be able to predict the mount point when someone inserts these thumb drives.