Personality can open doors, but only character can keep them open. -- Elmer G. Letterman

You can only get so far based on personality and charm alone. After that, you have to show what you’re “made of.” It may take some people longer to see through the façade, but it will happen eventually. That might be because a person has more charm, and lays it on very thick; or it might be that those around the charmer aren’t all that observant. Either way, it’s not going to carry you forever. That is the reason that some people move around frequently, be it in a job or a personal relationship. If they stay in one place too long, they get “found out” as that thin veneer gets chipped and worn.