Well, costs and timelines are always important. However, they must not be the dominant factor in the decisions. What we have learned over time is that investments must be made in order to reap the benefits of those investments. Spending more time to plan at the beginning of a project and taking the time to invest in good planning that will deliver the results is indeed a practice that should be put into place.
On June 14th, 2018. See this statement in context.