Some of the seams give the curtain enough volume in the upper part, where it is hung, and the other a minimum. Also, how easy to use is a curtain sewn in a certain way plays an important role.
A heavy fabric, if sewn with the straps, it pulled easily over the shower / tub. In fact, if you have to open and close constantly, it’s better to choose a shower / tub with rings that have hooks or pegs, barbed wire, with accessories, as well as a plaster or wooden curtain rod with a railroad.
Source
How to sew curtains
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