denied by an immigration clerk at the airport.
Poles get ESTA approval to travel,and are again scrutinized when entering the plane and advised if they will be refused entry.The CBP guard usually refuses entry if there has been serious mistake committed or the person has been unruly.For Poles who are refused entry are mostly the cases that they have already overstayed previously or have comitted a crime and coming back on a new passport.remember they have all the records from decades as one of my family members overstayed like most Poles did in 80s and tried to come back to visit her son in 2000s was issued visa but refused entry.Example of that again is when one of my relatives applied for citizenship he was asked to write about all the dates he left the country and came back in,and he didnt remember that,so his lawyer had to write to CBP and it provided every single date for the last 20 odd years of his departure and arrival (for a fee) for citizenship application.
That is for every visa waiver country.