It’s a very powerful way to align incentives. It results in a major reduction in political arguments and a major increase in productivity. It’s a long-term incentive, so it causes employees to take good risks for the customer even if they won’t be apparent today.

Stock is literal ownership and it eases “ownership problems” proportionate to the meaningfulness of the expected value of the stock to the employeee-owner. It’s a powerful tool for increasing teamwork.