Not sure what is the standard for checks taught here in Canada (trained in Australia) but I was drilled to check the gear 3 times. Lower and hold the lever until the greens on Downwind, again on base, then the PUFF check on short final.
3 checks of the gear, to avoid having a gear up...
That been said, I do believe that there will be some situations, circumstances or instances where it could be possible to miss, depending out outside factors eg emergency, workload, confusion