I think the analogy breaks down somewhat due to the relative scale of their misses vs. hits. A batter can only get so many runs with one hit, but a good investment can make all of the misses look like rounding errors.
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.
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.