Why do England make excuses?

The English bowlers only managed to take one wicket on the second day of the current test and all their commentators can say is the sun was out so the ball did not do anything firstly when they thought the ball was not doing anything Vaughan persuaded the umpires to give him a different ball a tactic that the English seem to use when ever they feel the ball is doing nothing and that ball offered some swing and also the second new ball also offered swing and seam movement so why was the excuse used that the ball did nothing for them why can't they say hey we didn't bowl as well as we should off and SA played us very well and were very disciplined unlike England who slashed at everything they don't even attack like that in odi cricket they need to give the opposition the credit instead of blaming the conditions