Comment by impulser_

My theory is the majority of the bad tech decisions made at these companies is mostly due to the high turnover rate of employees in these company.

The average tenure of a software engineer/developer is just 2 years.

People come and go and the next thing you know you're using 6 different database with services written in 5 different languages.

Instead if you kept the same 6 engineers around for decades you could probably scale to 100m with those same engineers.

It one of the reasons why it seems like Google can never release a product. They can't keep people around long enough to see it through.