If used correctly, yes.
Variations create an easier buyer experience, allowing the customer to see all product options on one page, instead of having to browse to see all the variations of the same product. It’s easier to buy a shirt when you can see all size options on the same detail page, rather than having to search for your specific size.
If used incorrectly, variations can cause confusion for the buyer. They can result in the buyer purchasing the wrong item, or misunderstanding what they are purchasing. For example, if your detail page says that the variations differ by color but they actually differ by color and quantity, the customer may expect to receive a different quantity than they ordered.