Why is it difficult for a bill to become a law

It is difficult for a bill to become a law because when a bill is being voted upon in either house of Congress, a majority of Yes votes out of all the votes being cast is required to pass the bill. The bill must be passed in identical form by a majority in each house, and then it is sent to the President. If he signs the bill, it will become a law.

It's difficult, because the congressmen has to introduce the bill in order for everyone to agree. Even when everyone agrees with the bill, the president can veto the bill.