13.11 Remember that almost everything will take more time and cost more money than you expect.
Virtually nothing goes according to plan because one doesn’t plan for the things that go wrong. I personally assume things will take about one and a half times as long and cost about one and a half times as much because that’s what I’ve typically experienced. How well you and the people working with you manage will determine your expectations.
* Source: Principles by Ray Dalio