Equal in chances...not results

In this case, the assailant survived and was (moderately) successful...and was a woman armed with a wrench.

In this case, the assailants, plural, were all men, and the one armed with a gun was shot dead by the homeowner.  They were not even moderately successful.

In both cases, the would-be victims were elderly. 

What was the difference?  The female assailant was smart enough to run up close and wrestle the homeowner to try to survive.  I'd bet the guys just...ran.  After the shock that their gunman was killed first thing. 

In either case, I think criminals are incredibly stupid.  They seem to just not even consider the danger that their chosen profession puts them in.