I'll give a different take. I started Tirz at 1.25mg, and bumped it up slowly on purpose. I did 1.25mg every five days for like, a month and a half, then went to 1.66mg every five days for about two months. 1.66mg every five days is basically the same as 2.32mg weekly, for perspective. I barely felt anything – just a little less hungry and some fullness. I dropped about 15 pounds in three months. I seem to lose weight slower than other people, 'cause even now on higher doses, I'm only losing a pound or so a week. The weight loss is so gradual that no one has noticed yet...except my closet, lol.
So, yeah 1.25 can still work, but I probably could have gone up sooner. My main thing was to avoid increasing the dose by more than 50% to try and keep side effects away. From what I've read, the 2.5mg to 5.0mg jump seems to cause issues for a lot of Tirz/Zepbound users, and I wanted to skip that. I probably would have been fine on the regular schedule, I usually handle meds well, but going slow meant zero side effects.