A VC is willing to take 20 flops to get one breakout bet.
Vetting a VC only by wins is missing quite a bit of information, presumably. It can at the very least tell you about potential blind spots and some idea how much actual skill may be involved versus luck or even "a broken clock is right twice a day" scattershot portfolios.
A batter can help win a series, especially the World Series, and make all their losses look uninteresting. But you still are going to at least check their batting average if you are looking to trade them.
A horse can win a major stakes race, such as the Kentucky Derby, and bring in a massive purse (and eventual stud rights) that makes any losses look like warmup rounds. But before heading to the betting window you are still going to check if they've lost any big rainy races if it's raining on Derby Day.
A Halo player can win a championship or tournament and no one will question any losses they've had. But you still are going to want some idea of their kill/death efficiency before scouting them for your team in the next deathmatch.
That .300 is considered good today based on the current environment of the sport and in comparison among peer groups. That same .300 looks shabby in a previous era or in particular sub-leagues or among particular types of batters (your benchmark for designated hitters might be higher given their only focus is hits, for instance).