I've heard from lots of knitters who don't like swatching. I'm never really sure that I truly understand why. After all it's still knitting isn't it? I do get that everyone wants to jump into the project and how excited they are to start.
I think of my swatch as a story board. It allows me to test out stitches in a small scale. I can experiment with the details. I can see how two stitches look side by side or test increases and decreases. I like to see how they work with a stitch pattern in advance of the project. I can add a little band and see if the stitch ratio for pickups is correct. It gives me a chance to understand the fiber I'm working with. Rayon and silks behave very differently than wools. Yarns can bloom after washing. I once made a tassel for a bag that surprised me when the strands untwisted all the way to the knot and the tassel became fluffy while the bag stayed smooth and firm.