The public doesn't realise squat. If it did, this show would have tanked after the first series. As for legitimately talented people, there have been quite a few of them on the show over its course. Strangely, most of the purely talented ones haven't made it through (well, it's actually not that strange), because the competition isn't geared to find particularly talented people, but people who would be enormously popular. Remember, it's backed by the world's biggest record company. They aren't interested in talent, they're interested in a marketable product. Quite a lot of the people who've been on the show have used it to get some attention for themselves, and in a few cases it's worked.