This would benefit from some examples of perceived "good" user experiences in this space. Also it's a bit lacking on the stateful side of things. For example,

This would benefit from some examples of perceived "good" user experiences in this space. Also it's a bit lacking on the stateful side of things. For example, a lot of Amazon customers hit "save card details" and then bam, one click checkout forever; making optimisation in this area highly diminished. Similar story and even more true for vendors that support Apple Pay.