the reason he was saying that was because he had such a high expectation on himself, so he is not satisfied with what he has done and what he is doing and probably what he is, but does not necessarily means that he is using the kid as an excuse, all he was doing was expecting more from the kid which most of the parents are doing in term of giving the kids more opportunities to be having a good life and education in the future, plus sometimes eventhough parents using kids as an 'excuse' may also mean that they, the parents, bear more responsibility rather to have their 'own' lives only, that's how and why kids depend on parents, rely on them and trust them as well, kids are part of your consideration towards your so-called 'own' life, you could not have your pure 'own' life once you become a parent, you, yourself, are a piece of the puzzle, not matter how big or small the piece is, you are not a whole single piece anymore, period.