A couple of other comments have noted, and Brendan Eich himself actually replied on Twitter (https://x.com/brendaneich/status/1944156296212886005?s=46 https://x

A couple of other comments have noted, and Brendan Eich himself actually replied on Twitter (https://x.com/brendaneich/status/1944156296212886005?s=46 https://x.com/brendaneich/status/1944156296212886005?s=46), to say that it was a copy of Java’s Date class behaviour. I haven’t dug into the history of that, though.