[mkagenius]

You are right. Betting everything on a 6 digit code surely is a mistake. For example, try same code on a million different account, and you definitely get access to atleast 1 of them. (Considering they are using a good random generator)

[SifJar]

You probably get access to at least one of them, not definitely

[wz1000]

There is a 36.7%(or ~1/e) chance that you don't get any of them.

[mkagenius]

In case anyone is wondering that can also be derived like in the birthday problem - (999999/1e6)^1e6 .. which is not 0 but 0.36787