There is no doubt that in order to become a great tennis player you must have some talent. Whether its being very quick, having great anticipation, being able to read the ball or being able to generate easy power, players usually have a specific talent. For example, Nadal has an unbelievable acceleration and work ethic, Federer has easy power and great anticipation and Djokovic is very quick, solid and smart on court. Talent is very important yes, but all of these talented players have one thing in common, hard work. Things didn't always come easy for them in fact, Federer couldn't win matches when he was 15, he would break rackets and have a bad attitude out on court. It was only until he made the decision to change that he started to reach his real potential. Federer says that it wasn't until he saw himself in video that he realized how foolish he looked on court.
There are always certain parts of the game that players may struggle with, even Federer. This is why "Talent without hard work doesn't work". How many times have we seen a very talented 14 years old hitting big forehands with loose hands but with lazy footwork and a crappy attitude? There is just no way around it no matter how talented you are. You need to work on your weaknesses as hard as your strengths and you need to push through your limits in every practice and match.
There are always going to be obstacles on the way, bad days, tough loses, but that doesn't mean anything in the long run if you learn from your mistakes and try to get better everyday. It is about how fast can you recover after a loss? How are you going to solve the problems on matches? How resilient are you willing to be in order to achieve your goal?
"The biggest limitation a player has is how big the wall is on their minds" Can I do it? Am I good enough? What if I fail? The answers should be: Of course I can and I will persevere until I do it. Of course I am good enough this is what I practice for and I certainly deserve to win this match. There is no failing if you try your hardest, only gains.
I have seen many players without major talent that have become great players with hard work and perseverance. It's an attitude, a mentality to be the best. Having that kind of attitude is also a talent, not everyone has it. It is rare these days for junior players to be able to be focused on court, listening, positive, working with intensity, and pushing to their limits. It is safe to say that as long as there is some talent in there, the rest can be developed with a good work ethic and determination.