Hello,
If they order 300, yielding 21lb package, it will quote $57.34 for the shipping via UPS Ground. However, logging onto UPS's site directly and shipping a 21lb package comes to about $32, instead.
This quote is based on the fact that you are ordering
300 products, in that case, the UPS shipping plugin is trying to group every products ordered on packages regarding the UPS limitations, so maybe the price difference is coming from the fact that
UPS have its own way of grouping products into several packages.
Note that our UPS group packages algorithm is optimized to efficiently group the ordered products based on the size/weight limitations that are displayed on the UPS documentation, and after that, the UPS plugin will only display the rates that are returned from the UPS platform.
If you want custom made rates starting a number of products added to your cart, you can for example use a manual shipping plugin starting 200 products ordered for example, so that you can manually set the price.