Just received my new white joint account card to discover the new design doesn’t have “joint” on the front. It’s discretely written on the back but that’s not useful when pulling cards out of my wallet.
Please please please….. put “Joint” on the front…. Please 
When I pull my cards out of my wallet, I can tell my personal card and joint card apart because one is bright orange and the other is white. Unless I am misunderstanding this, why would you need the word “joint” on the front to tell them apart. 
Personal preference I guess!
Just makes it more obvious as I rarely use the physical cards (I usually use Apple wallet …. Which does actually have the word “joint” on the card) and I’ve had various coloured cards recently so….. why not?!
Not sure if you’re wanting an answer to the “why not” but the reason is likely cost related.
I think if both cards were the same colour then this would be a great suggestion as it wouldn’t be obvious to tell them apart, but as they’re both different colours I don’t think this is necessary. Obviously this is just my opinion though.