Permanent standard time means less sunlight time after work.

Permanent DST means kids walking to school in the dark.

Changing the clock twice a year fixes that and lets us avoid both, with the only cost being people complaining for a day afterwards. It's like ripping off the bandaid, instead of doing a slow agonizing pull that lasts months.

And yes, I know some people take like 6 weeks to adjust and they will complain incessantly to stop it, but for the whole group, the least painful thing (I'd argue by far) is just moving the clock an hour.