Additive Domains, Multiplicative Domains

In some domains, the results of your work are (something approaching) additive. If you have three main inputs and your scores on those inputs are 3, 5 and 7, your final score will be 3 + 5 + 7 = 15. If you want to increase your overall score, the only thing that matters is adding extra points to your inputs – it makes no difference how you distribute them, it's just more = better.

In other domains, the results of your work are (some complicated function more similar to) multiplicative. In multiplicative domains, having any week scores will hurt you. Obviously the best thing of all is to increase your score on every input, but if you only have 15 points to distribute then 5 * 5 * 5 = 125 is better than 3 * 5 * 7 = 105 and certainly better than 1 * 5 * 9 = 45. If you have limited ability to improve, you're better off adding fewer points to your lowest score than more points to your higher scores.

Actually applying this to your real life is not easy. Real life outcomes are neither additive nor multiplicative but rather a third, secret, far-more-complicated thing. What's more, the available conversion rate between "adding points to your lowest score" and "adding points to your better scores" is not known or obvious. Also-also, in real life the game you're playing isn't fixed: maybe you can find some other game that doesn't require your weakest score at all, or you can work with someone else whose strengths fill in for your weaknesses.

But still, multiplicative domains provide a theoretical model for why (and when) working hard to improve your weaknesses, rather than double down on your strengths, might make the most sense.