Meritocracy makes people feel their failure a lot more, because they believe they are entirely responsible for it. This in turn makes them feel more shame around failure. Botton talks about the art of failure and gives some great examples, including Hamlet, of those who have lost, but not failed.
Plus, I think we can all say that there isn't really a true meritocracy anyway, as there will always be both visible and invisible privilege. So how do we measure success? What does success mean to you? How will you know you've achieved it?
In the end, we all need to define success in our own terms. It's hard enough succeeding, Botton says, let alone being unhappy with the result if it's something you never really wanted anyway.