Mental toughness is many things and rather difficult to explain. Its qualities are sacrifice and self-denial. Also, most importantly, it is combined with a perfectly disciplined will that refuses to give in. It’s a state of mind – you could call it character in action.
Success is like anything worthwhile. It has a price. You have to pay the price to win and you have to pay the price to get to the point where success is possible. Most important, you must pay the price to stay there.