Do you alter your patterns or make your own patterns?

i've altered patterns a couple of times. there was a dress i made awhile back that i used the sleeves from a different dress pattern on it because i liked them better. it came out pretty good, but i had to adjust it to make the sleeves fit the armhole.

I pretty much do my own thing when it comes to sewing. When I was younger my mom always had us use the patterns but now I don't. I just either go by eye or I take the measurements of the person I am making the thing for. I have had a pretty okay success rate when it comes to not using a pattern. I mainly make children's clothes and items.

I've done things like combined two patterns to make something different. I've also altered patterns. But I haven't actually made my own, nor have I actually sewn an actual garment - mostly costumes and craft stuff. I imagine garments would be more difficult to acheive success at altering.