If you want to be a successful trader, greed is probably the biggest obstacle you will have to overcome because Greed is one of the biggest enemy of trading and practise with proper discipline and right mind set with self-control will help you to overcome this negative emotion.
Greed is obstacle and your big enemy which can spoil long days of hard work in few seconds. Always try to make everything normal that will enable you to get some profit from here conversely if you take it and greed for it then you may not be able to get it.
If we discuss about perfect time then it is a better decision to wait for the price to go higher so that you may be able to get huge profit which is relevant to say.
Greed can destroy you in this market, you could be a very good trader that can predict with some degree of accuracy how the market is going to move and make profits in your trades, but if you choose a size for your trades that is simply too big, then even if you have a winning system you could lose all your money simply because you are not capable to endure a few losses.