Even the most successful entrants have hardly ever made it past the first album in the past decade or so. The exception is American Idol. As with Wikipedia, there's nothing wrong with it. The problem is its centrality.
More people appear to vote in this pop competition than in presidential elections, and one reason why is the instant convenience of information technology. The collective can vote by phone or by texting, and some vote more than once. The collective is flattered and it responds. The winner are likeable, almost by definition.