It’s when an established vendor stops sending product but continues taking payments as long as they can. There is a period of time where their reputation means continued sales before the community figures out that they aren’t being sent any product. Often coincides with a big sale in order to drive as many purchases as possible on the way out. No reason to believe nexa is doing this right now just because their site is down for a minute,
@peptideusername can be a little quick to jump to conclusions sometimes