Why are my validations hidden? When do they become hidden?

Why aren't my validations showing up? Can my customers see them?

There are two types of validations. There are the "alert but continue" (yellow) and the "alert and stop processing" (red). Your customers will be able to see both of these validations, however the "alert but continue" (yellow) validations will disappear once an order is verified. At this point customers will no longer see those validations.