You could also use the expression "perfect is the enemy of good".

Sure the perl engine is not that perfect (in fact in many respects its a heap of steaming excrement that happens to work only because some guy named Zaphod and the Infinite Improbability drive happened to be passing by at the time it was compiled), but its good enough, has proved itself to be a powerful tool and has done more than all the other regex implementations put together to advance the programming communities knowledge and exposure to regular expressions.

Also given your link I find it amusing that rsc is from MIT. :-)