Mark Knopfler

Hammer down product fundamentals first. Make sure you've got something that works before doubling down on promotion and marketing. Create a groundswell of organic support, and only then leverage PR and advertising to spread the word.

There may be some backward countries where the mass of the people are on a subsistence level and where, as an aftermath of wars or partial crop failures, the standard of living has to be drastically reduced, but this certainly is not the case in our prosperous nations.