They agree to trade the surplus value they create in order to have a job, and receive a ratio of that surplus value instead. This is because they know they haven't the capital, nor the preparation to do otherwise.
If they owned the means of production, they probably wouldn't work so hard as they'd have a relatively larger slice of the pie.
This means the "efficiency of Capitalism" comes from the exploitation of workers. It it only because the full surplus value is kept from them, and they have a knowledge that they can be fired, or have their lives made difficult by "superiors" that they can be worked so hard (aka "efficiently").
Finding a better balance or third way structure, would require finding a way to motivate people, whilst also rewarding them AND not exploiting them.
Perhaps workers could be arranged to keep each other in check. Perhaps there's some other structures that facilitate freedom, a lack of alienation or exploration, whilst retaining motivation... That's what's needed... Comfortable, unalienated labor, that is desirable, and efficiently structured.