This is a good question and I guess no one knows the answer to it for sure, not even those who are forced to make the decision. How often we see athletes winning every competition they participate in, then their performance start to deteriorate and after a time they are not able to get on the podium.

They say you gave to get out when you're on top but when is that? This is a tricky thing as after a failure you think that was just an unfortunate event and you'll do better next time. Then next time things go wrong again but you're still hoping you can get back to the top. This can go on for awhile and then you realize you should have quit a long time ago.

It's definitely not an easy decision and once the decision is made, there's no turning back. Or wait, there's turning back as many have quit and came back, some more than once, others all the time.

Female gymnasts tend to quit or retire at a very young age as that's a sport where at 21 you're already old and can't keep up with the young ones. However, some gymnasts are choosing to come back and compete only at one apparatus. They are lucky as there's this option available for them. Others, like tennis players can't choose, tennis is tennis, you either play it or you don't. Nor can runners.

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The other day I was reading about Shelly-Ann Fraser-Pryce's interview, in which she says Bolt (my all time favorite) quit too early. I was a bit surprised as the only one who knows if it was early or late is Bolt himself.

I've been watching interviews with him and know what he's been through with injuries and different challenges. He said in one of the interviews that there comes a time when you have to work twice as much for that result and it's not fun at all. He's right, I fully agree with him as he's body is not getting any younger and when it's not fun anymore, you need to make a decision.

He decided to retire when in 2016, at the London's Olympics he could not get the gold, he only came third. I can't blame him, I'm fully convinced he took the right decision. It's better to be remembered for your winnings and not for struggling and failing each and every time.

Serena Williams seems to be the other example, who's struggling to get back to the top, without much success. At the moment she's risking to be remembered for these failures and that's not good. I don't believe she can get back to the top again to be honest. There are so many young players that a very good that her chances are slim to none. There's not much information about what her plans are or I haven't seen any but my guess is this is her final year in tennis. We'll see.