@Ramenator I think sewing is the best way to get a neat finish in many cases

I agree with Venite. There are often holes in places where multiple seams would meet in a sewn garment. I mostly knit sweaters and I pretty much always take some time tightening things up around the armpits, with very rare exception when it’s a particularly good pattern. Just is what it is! If it’s inside, it doesn’t even have to be neat because no one will see it, so just sew up what you need to tighten.