The sales of garments depend to a large extent on the market research done before finalizing the designs, sizes

The Amazon brands for womens clothes Myx, Tavasya are well designed and affordable.
However a major problem is that they are only only available in XXL size, which is 42 inches or approximately 105 cm according to the size chart
While it is not clear how they decided to limit the size to 42 inches, they are leaving out a large market of women who would otherwise purchase the kurtis

Most of the women who wear kurtis in India are older women above the age of 40, most younger women are wearing tshirts and western clothes
For example goan bhandari fraud R&AW employee sunaina chodan, almost never wears indian clothes, she wears only tshirts, shorts, dresses, jeans, shirts. Due to the decline in the metabolic rate, most of the women in India above the age of 40 are not very slim, they require 44 inches or a bigger size.

For the clothing manufacturer providing a few more inches in the garment, is not very expensive or difficult, but for the customer increasing the size of clothes which do not fit is very difficult, it is a waste of money. So most women prefer to purchase a larger size of kurtis, so that their money will not get wasted, because the size is very small.
Getting clothes stitched by tailors is very expensive, they are charging Rs 350 per set, while online some kurtis with material are available for Rs 300 or less, which can be used for daily wear