Bus drivers observe me struggling to get the card to register until I give up and pull it out of my wallet, even though the readers are generally capable if reading it through one thin layer of leather. Rarely a driver will break the silence and offer a bit of advice that turns out to be genuinely useful.
On my own I figured out that the chip in the card is near the top of my wallet, but I didn't know until a driver told me that moving the card (and my wallet) more slowly toward and over the reader would help read it on the first pass.
Likewise, I didn't know until today that the reader is located on the right side of the pad. I have a tendency to hold my wallet near the middle of the pad, which probably explains why I've been having problems getting my card to read properly. And this knowledge would also end up being a benefit to the drivers if they shared it more readily with passengers, because faster card reading means faster boarding overall.