Throughout the movie, Frank Abagnale Jr. has multiple pressures that cause him to commit fraud, opportunities to commit them and rationalizations about them. These three factors all end up causing him to commit the fraud and to escalate it, some more than others.
Most of the pressures that Frank goes through in the movie would be in the financial pressures group, and a little in the other pressures group. His first pressure in the movie would in the other pressure group. When he arrives at his new school and can tell that he doesn’t fit in, that pressures him into posing as the substitute teacher for the class so that the other kids won’t pick on him. Pretty much every scam from there on involves financial pressures, starting after he runs away from home and begins to impersonate a Pan Am pilot and forge payroll checks. Later on in the movie, Frank has a pressure to stop the fraud because he is getting married and wants to settle down but because he has already stolen so much money, the only option is to continue being on the run and continue the fraud.
Probably the biggest part of Frank being able to commit these scams is how many opportunities he has throughout the movie. Starting in the beginning at the school, he sees that the teacher hasn’t arrived yet and uses that opportunity to pose as the substitute teacher. It continues when he poses as a school reporter and uses that to get info about being an airline pilot, even getting an expired FAA license when he asks if he can make a copy of it for the school paper. Another opportunity he has is when he is nearly caught at the hotel he is staying at, but poses as secret service and uses the elderly man who is getting helped into a car as the caught suspect and escapes.
Franks only real rationalization in the movie is that he’s only doing it so his parents get back together, like when he buys his father a new Cadillac and suggests that he takes a drive with his mother. Other than that, he doesn’t really seem to rationalize what he’s doing. He just keeps doing it because he can and keeps getting away with it.
In conclusion, many of the scams and frauds that Frank pulls off involve all three elements of fraud, pressure, opportunity and rationalization. While some use a lot of pressure, others use a lot of opportunities, all having their effect on Frank in the course of the movie.