I think that's the time to scan both sides of the check (which is not done with a photo scanner, but with a sheet fed scanner, so it's not instantaneous), uploa

I think that's the time to scan both sides of the check (which is not done with a photo scanner, but with a sheet fed scanner, so it's not instantaneous), upload the image (potentially over a very slow network link), add it to the OCR queue on the server, do the OCR, save the image, and return the results back to the ATM machine. I highly doubt the ATM maker put in sleep calls to intentionally slow it down -- no one is going to be surprised if it takes 1 second instead of 10 seconds to scan a check. The bank could optimize for time, but it's not their time, it's their customer's time and they are already saving so much money over a teller transaction, they likely don't care about saving customers a few seconds.