Their shareholders are not in it for the long term. Investment managers tend to look at anything more than two years as "long term", and they are conscious of their position in annual league tables.
Even private equity and venture capital are usually going to be thinking about the value at which they can exit reasonably soon.
The management of the company will be thinking about bonuses and options they get between now and when they move to the next job.
A private company can often take the view that what really matters is how much they will be making in five or ten years time. Maybe even how much it will be worth when the current shareholder’s kids inherit it. The management are often either owners, or are closely monitored by the owners.
tldr; GTFO!
In many public companies there is the added level of investor interest, and it can often be a challenge for the C levels to remain in power during periods of slow or even negative growth. Challenges that companies like Valve simply don't have as long as the CEO is fine with it. On the flip side, I'm happy with my own stock portfolio so there is that.