[testing22321]

ESTA is just the authorization to apply, nothing to actually get you into the country.

With an ESTA in hand, an eligible visitor must get an I-94 visa waiver at the border for $6. Even with a valid ESTA this can be denied.

Source: at this point I’ve had 4 dozen of them over the last two decades.

[rwmj]

You can be denied at the US border if you have a full and valid visa. The only way not to be denied is to be a US citizen (so far ...)

[briandear]

That’s true with any country.