We have never failed
You did not become a scientist immediately after your fifth standard. This does not mean that you failed in school or the 5th standard was not necessary. It was just a stepping stone or a link in the chain. We say we have failed when things have not worked out. They are not failures either. They are just like standard five, nine or twelfth in school, stepping stones or just a link in the chain. Without links a chain in impossible. Even if one link is taken away, the chain becomes defunct.