Burnout often comes from being responsible for things you cannot control. This is why, for people who advise for a living, guaranteeing results the client will get as a consequence of the advice is a really bad idea.
But that doesn’t mean you cannot guarantee anything.
Here are a couple of ideas that I tried out myself:
1. Guarantee of integration: my advice will be compatible with the systems you already have. Without compatibility, even great advice can be just a dead end.
2. Guarantee of communication: I will make sure you know everything that you need to know without you having to ask. I will also remove all ambiguity and jargon that I possibly can, draw conclusions, and propose the next steps.
3. Guarantee of timeline max: A tricky one, but if the timeline is a priority for you, I will do everything that can be done in the given period. When you get out there and present results, you will be sure they are the best case that could have been made in the circumstances
4. Guarantee of transparency: When the results come, you will be able to challenge any part and get a clear and satisfying explanation based on data and professional best practices.
These may be scary to give, but the high stakes are what makes them valuable in the client’s eyes. In contrast, empty platitudes cost and risk nothing to say, that’s why they are worthless. If you are able to promise any of the above, do it.