Where do you draw the line of dumping someone when they do not deliver? Personally, I also don't know the answer. Bigger problem is when it is an established player. I.e. Boucher or Ntini. How many games do we allow them to play before dropping them.
Do you give someone 10 / 15 / 20 games? If you don't meet your KPIs by then you are gone. Imagine we dropped Kallis after 10 tests. He was a good enough player that would have made it back, no doubt.
I feel for selectors. Does not matter which players they pick, there will always the balance of meeting certain requirements, crowd favourites, etc.
Look QdK was picked and he really struggled over several games before he came right, just like Abbott & Rilee now. But QdK at least managed to look like a world top 15 batsmen after that patience was extended.
Certain things also come into the mix which is why players don't get groomed consistently enough. Player similarities. Abbott had a great start to his Test career but couldn;t build on it. Why? He's a bit like Tsotsobe&Philander. Medium pace, relies on swing. His only disadvantage is Philander swings it more, while Tsotsobe has height advantage on release, left handed and like Philander swings it more than him. If he had continued bowling in Tests who knows if he wouldn't have done well. Marchant being a tall, express pace strike bowler liek Morkel meant you could only have one at a time not both.
So you have to blame the selectors in many ways. Philander was consistently dropped form T20s&ODIs for the same reasons Abbott is struggling yet they still picked Abbott. Morris & Rory were dropped for the same reasons, and recently McLaren. At no point has Abbott look significantly better than them so why did he get the nod?
Same applies to Marchant. Great start to his career standing in for Philander when he was injured. At the time Steyn&Philander were by far and away the best. He should've continued but he didn't because no one had the gonads to drop Morkel. The 2nd time Marchant got a chance Philander had already destroyed NZ after Alviro had led to setup a huge score. NZ were set to chase an impossible target with no time left, and lo and behold a Morkel fighting for his place was given the new ball, marchant wasn't. Rest is history.
For other it's just downright bad luck. Viljoen go many chances for the A side probably more than a lot of seamers. He never delivered in any of them. Who knows if other like Abbott had also played similarly or more would they not have been found out at that level an dnot allowed to go further?
The only thing I ask of the selectors - as well fans - is that the same patience shown to the like of Abbott, QdK, Ingram&RR be given to EVERY other player. 15 game shas clearly been the average.