In the days before leashes it was a common occurence to lose boards out to sea, when surfing outer reefs. Ventura Overhead claimed a few. Take a wipeout, come up, swim in, and no sign of your board. The rip channels would carry them out to sea, probably wash up somewhere, some day.
When surfing good sized Hookipa way back in the day, before the kitesurfers took it over, I lost my board and had to swim in. The rip channel there (at that time) was right in line with the tiny little stretch of sand, the rest of the beach was jagged lava rocks. The temptation was to try to swim in where the sand was, which I did. But the rip would carry me out again and again, I could never get near.
Some people on shore saw my plight, and pushed my board out to me by putting it in the rip. Only I didn’t know. I could see a crowd on the cliff shouting at me and saying something, but with the roar of the surf I couldn’t hear a thing. Eventually I just swam up to the rocks, waited for the last wave of a set to blast against the rocks, then scrambled like heck to get up and out of the impact zone before another blast. Made it, only to find my board was drifting out to sea, past the breakers.
I was wore out and didn’t feel up to swimming back out at that point to get it, and it was drifting into unfamiliar territory quickly. So I got in my rental car, and started driving down the coast, following the bobbing yellow spot just beyond the breakers. I would pull over, watch it drift, then drive a little more, and do the same, figuring it might wash in.
Eventually, a local with a lot of aloha and a big opu and some swim fins saw my plight, and looked out at the board, “hey Brah, that your board? I go gettum for you!” Swam out past some good sized breakers like it was nothing, nabbed my board, paddled it in and handed it to me with a big grin on his face. I couldn’t have been more thankful, but IIRC a twenty was the best I could come up with, told him mahalo go buy yourself a six-pack brah.
When I was a kid I used to fly model airplanes, the kind you turn loose and let 'em go. Sometimes they would ride a thermal, and disappear into the sky. We would rig a timer, usually a rubber band with a small piece of burning rope in it, so that the rope would eventually burn through the rubber band, and the stabilizer wing would pop up, causing the plane to spin down gently.
But that didn’t always work, so we would generally put our name and phone number on the plane, in case anyone found it they could contact us. I got a phone call on one months afterwards, from a farmer who found it while harvesting his corn. The plane was wasted, but the little engine was still good! I guess if you’re gonna go leashless in bigger waves or outer reefs, might not be a bad idea, ha!