"I have not failed. I've just found 10,000 ways that won't work."
I think that this quote means that every inventions that he has made are not failures. They are just building blocks for success. He is also saying that we should keep on trying and trying until you find the perfect one, which not considered failure.
"Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time."
I think that this quote is trying to say that if we do something and it doesn't work, we should just keep on trying and hopefully it will work out. For example, if something is being built and it keeps on failing, building it again will help instead of giving up on it.
