If you can see the shop you will most likely get it. If you can not see the shop and you get an email it's most likely that the shop is rated above your rating level but they are having problems getting it scheduled. So yes, someone else replied quicker or had a higher rating or is someone the scheduler was more familiar with. Just do 3-4 shops, do them incredibly well, and make absolutely no mistakes. You will begin to see some of those shops on the board and be able to get them.