[markbnj]

They probably didn't have the ability to test it on nearly enough readers, given that there are literally thousands. They may also be running into some timing issues based on how people swipe. Those are things you sometimes just can't work out barring wide scale testing and adoption.

[Someone1234]

Right. But file this away in the "not my problem" draw. You can make all the excuses you want, but this is ultimately up to them to resolve, not for the consumer to deal with.

[maxerickson]

A comment here indicates that it simply won't work at a bunch of retailers:

http://forum.xda-developers.com/general/off-topic/coin-vs-pl...

A quick search confirms the caveat:

https://support.onlycoin.com/hc/en-us/articles/204413864-Whe...

(first link noted from a previous discussion here: https://news.ycombinator.com/item?id=9879699 )