What do product marketers get wrong when trying to influence the C-Suite?
Product marketers most often come up short in influencing the C-Suite by showing up at the wrong altitude, with the wrong information and the wrong disposition. The most common mistake I've seen is a PMM showing up with far too much detail and data without a clear "here's the goal, here's what we know/learned, and here's the 'so what' of if all." No one in e-staff is going to read your 15 page messaging brief or detailed launch plan or expansive customer usage report. You have to synthesize all of these things into "Big Animal Pictures" (a great term I learned early in my career) to effectively communicate cross functionality at the highest levels of the company. You need to present something with a "so what" and a point of view that will make as much sense to the CFO and head of Legal as it does to your CMO. If your C-Suite is following the Amazon 5 page brief model, write a water-tight 5 page brief. If you show up with slides, be ready to present 2-3 slides at the most with the additional information on hand in an appendix. These are insanely busy people with massively complex problems on their plates at all times, so you have to be clear, be brief, be good and then be gone. That's hard to dial in and takes a lot of practice, so ask for help and feedback when you get those opportunities.
On the flip side, you also don't want to show up with e-staff with a blank canvas of open-ended questions, problems without proposed solutions or the intention to "brainstorm" on your topic. I've both seen and lived that before and it doesn't end well, trust me. To build confidence in your work and, really, yourself, show up with a tight synthesis of the topic at hand including your recommendation for the path forward that demonstrates your understanding of the details without asking everyone in the meeting to delve into the nitty gritty.
Finally, don't make it a performative display of how smart or experienced or valuable you are. Execs can usually see through the Project: "Look at Me" nature of those displays and it will do exactly the opposite of what you'd hoped. Make the work awesome and it will accrue back to you.