Sales techniques: does one size ever fit all?

Just finished reading another sales book. I make a point of reading a couple each year, always curious about new techniques and what the data supposedly confirms works.

My first proper sales training was about 25 years ago—SPIN Selling. The whole BDM team spent two days deep-diving into it, role-playing, and refining how we use it to engage stakeholders and collaborate with practitioners to win more work. It was structured, logical, and based on research. But was it the method? Not really.

That’s the thing. Every sales book has its own methodology, its own ‘proven’ approach. And yet, in practice, I’ve found that what works varies—between industries, teams, clients, and especially practitioners. Some techniques resonate, some don’t. Some work in one scenario but fall flat in another.

One of the biggest lessons? Sales techniques have to feel authentic—not just to you but to the practitioners you’re working with. If a framework feels forced or unnatural, they won’t use it. And if they don’t believe in it, clients won’t either.

The reality? Don’t follow just one technique—build a toolkit and adapt. Pick up different frameworks, test them, refine them, and use what fits the moment and the people you’re working with.

So, I’m curious—what’s a sales technique you swear by? And have you ever found one book or method that always works?