Fabrication
The quality of fabric used to craft a sweater is a make or break moment. Specifically, the percentage of fabric type for any high-end item of clothing is carefully selected and tested. Would 50% cashmere and 50% synthetic lend a better stretch? Let's make a sample and see. Would 80% natural fibers and 20% synthetic feel more luxe? Call the manufacturer and have them make a sample. Each time a sample is made, more money is spent and getting a fabric blend correct is essential. Look at the tag of the top you're wearing, normally found on the inside of the side seam. My current Jason Wu is 40% wool, 33% viscose, 14% nylon, 11% PBT, and 2% spandex. Woah. I bet it took a few fittings to get that blend just right.
[Photo via @places_and_spaces]