What are some things that seem logical on the face of it but actually defy common sense?

Some of you know about my saga of two days without running water. My husband just got it up and running about 30 minutes ago. He had to change out quite a bit of the plumbing to the tub, as well as the bath tub fixtures, including the shower head. But he finally got it done. So, I excitedly got ready to take a shower. The pressure out of the faucet was good…but when I diverted the water to the shower head, the pressure wasn’t half of what it used to be. I asked my husband what was up with that. He said it has a “limiter” or “restrictor” or something in it….it’s supposed to save water.
Needless to say, it took me twice as long to take a shower than it used to.
How is that saving water??

He said he’ll take the restrictor out. : ) BAD husband! YAY!!