A pro's career is very short so the decisions have a larger impact, because it's impossible to go back in this sport.
Often a player will decide it is not his fault if he doesn't get the results he expects - he will always find a reason. But I believe professional tennis is very positive in the way it is fair to each of the players.
Rafael Nadal is the current world number one, and is re-writting the history of this sport for the following reasons: courage, devotion, personal investment, personal questioning, work ethic, love for the sport - the list could go on and on.
At only 23, Andy Murray is now at a crossroad in his career.
Over the past two years he has been at the same level and his future is looking darker than it once was.
Murray improved vey quickly up until 2008; he claimed five titles and reached the US Open final to become the world number four. And in 2009 he won six tournaments and finished the season at number two in the ATP rankings.
But now he needs to win a Major. Despite his runner-up spot in the Australian Open earlier this year, he is yet to win a singles title and seems to be struggling.
The fact is Murray is faced with quite a common dilemma.
He improved constantly for several years, never doubted himself and grew up with the belief that anything is possible. Ambition was the motive to work hard every day, until he came to 2009 and a crossroad in his career.
The Scot was sure he would win the first Grand Slam of the year until he faced Federer in the final sprint. 0He was clearly hurt after he lost to the Swiss once more in January this year.
He worked very hard but was defeated and then believed he would remain a top five player even if he didn't put in the same amount of work - he chose the wrong option and that's the difference between great players and good players.
However, I trust Andy. I'm convinced his mental strengths are huge. But he needs to be well advised as his current relationship with his coach is special.
He worked with Spain's Pato Alvarez when he was younger and had promising results but then had to split due to conflicting issues.
He then hired Brad Gilbert but again ran into a world full of conflicts, despite many successes which boosted him to a top-10 ranking.
These dramatic relationships forced him to build a team made up of 'friends'. The player then becomes the boss of his coach, his sparring-partner, his fitness trainer, and two physiotherapists.
But the Scot does possess great qualities. He has soft hands, which is unique, and excellent eyes which helps his return of serve as he can take the ball early as he wishes.
He also has great anticipation, one of the best backhand in men's tennis, a good serve, a good tactical mind and, last but not least, great fitness.
All of which allow him to have decent movement around the court and the ability to resist opponents' attack for long periods of time - which was not the case earlier in his career.
Add to this his thirst for competition, his mental strength ability to cope with pressure, and there is no reason why he could not achieve great things.
However, there are elements still missing in Andy's game.
No one in his team has so far managed to coach him on a daily basis.
All the past world number ones have a defined style of play, sequences they like to impose for winning their matches. We will always recognise the game of Andre Agassi, Pete Sampras, Roger Federer or Nadal because they have their unique style.
Andy can play many styles and that's why he is having issues with his game. The ability of having choices on a court in reality makes him play tentatively.
Some may wonder whether it's that bad since he is winning many matches by hiding his game and making his opponents play bad.
But that is precisely the key. Andy needs to select one style of play and stick to it - permanently - when playing the so called 'easy matches' against lower ranked players.
Then the 'Murray game' will be born.
More than ever, Andy needs a guide, a man full of experience and conviction.
The team he has with him clearly offers him comfort on a daily basis, which is very useful. So maybe the right formula would be to keep his team and add another key person.
Andy is still young but he must act quickly - if you stop the progressing you start to go backwards.
But he has a bright future ahead of him. He can do it - he must do it!
- Andy Murray
- Rafael Nadal