This is how the app selects the options to display to the shopper for the live shipping rates.
1. Cheapest option: prioritizes price over speed
2. Fastest option: prioritizes speed over price
3. Cheaper but still fast: Neither the cheapest nor the fastest; prioritizes price over speed but not so much as option #1
4. Faster but still cheap: Neither the fastest nor the cheapest; prioritizes speed over price but not so much as option #2
Basically we are picking a selection of rates that are cheap and slower, fast and expensive, and some that are middle of the road. We usually see 4-6rates but sometimes there will be less rates available.