Is MS Vista a failure?

MS Vista has become the major target of hackers, before its final release a lot of reports about is major flaws and serial cracks. Recently, Microsoft and independent security researchers, tried to play down the risk from the flaw, which was disclosed on a Russian site recently and is apparently the first affecting the new Vista system released to larger businesses in late November. Microsoft said it was investigating the threat but found so far that a hacker must already have access to the vulnerable computer in order to execute an attack. How come a multi million dollar worth of software cannot protect itself? Is Vista a major failure?