Who owns messaging in your company?

I've been thinking a lot lately about how the main challenges startup founders deal with have evolved in time. After talking to a couple of them I realized: The focus has changed a lot. In the past, you'd have founders worried about how to get their first 1000 customers. These days, they know how. Whether that's content, community, outreach, social media, etc. But they've realized where the core problem is: Poor messaging. [and, if you ask me, this often also ties with poor market positioning] One of my goals is to make founders understand where messaging truly lies. That's because the way you define your brand and products doesn't just show on your homepage and product pages. It's part of the entire buyer journey. I'm strongly advocating for researching and outlining your users' journey as you define your messaging. Pairing this with user research gives you a good overlook over where your ICPs spend time, what they want to see, and what kind of messaging appeals to them. As a side note: I'd also recommend defining jobs to be done at this stage and updating this framework as you launch new features/use cases. I'm a firm believer in getting the messaging right from the beginning but I'm also aware that sometimes you'll need to launch with an initial messaging. Not always the best one though. Can a good product marketer save the day? Who owns messaging in your company? Is just reiterating on your initial product messaging THE best practice? Curious how you'd handle defining (and maintaining) messaging for a startup. Do keep in mind the different stages a startup can go through.