Smaller Capacity Memory Cards

[Run&Gun]

Ok, so for the most part memory cards have usually come in capacities of 8GB, 16GB, 32, 64, etc. But now I'm seeing cards in "weird" capacities and trying to figure out why. For example, a few years ago, Panasonic stopped making P2 cards in 32GB and 64GB capacities and they became 30GB and 60GB, but P2 express are still 256GB and 512GB. And I just noticed Sony doing the same thing with XQD. 128GB G series cards are gone and have been replaced with more expensive 120GB G cards. 256GB G series are still available, but now so are 240GB G series that cost more, but are rated/spec'd the same.

So I guess my question is the obvious "Why"? Is it the go-to of money? Have the chip makers found a way to make the memory chips slightly smaller(capacity) for less? New manufacturing techniques that yield less memory capacity? Something completely different or a combination of things?

 

[Jarek Zabczynski]

It's for overprovisioning. A 240GB is really 256GB but only allotted 240GB for use. When blocks on the SSD go bad they get "replaced" with the spare ones. That's a bad explanation but that's the gist of it. That's why you are seeing sizes just slightly below the "norm".