How do you align executives and stakeholders around messaging, when it's very subjective and subject to debate?

You need to listen to people, share positioning work as it develops and be iterative. If you just show up with a messaging strategy without involving leadership in the formulation you are most likely going to get pushback because everyone thinks they know what we should be saying to the market. But if you take time to listen to people, and shape the messaging in response to their feedback people will be much more likely to agree. It goes back to that old adage that you should never show up to an executive meeting presenting something for the first time - shop it around beforehand. The same applies to messaging.

The short answer is customer validation. The best messaging is what comes out of your customer's mouth so spend time learning from your customers and informing your base messaging. But even after you validated your messaging, test it. Run a/b tests in digital, email, and other channels to show you what's resonating, and use this data-driven insight to continue to refine your messaging. Bring all of this data to your executives to create the needed alignment. 

Building strong messaging, aligned across executives and stakeholders can be done using 3 key tactics.

1. First, include and cite trusted datapoints, both qualitative and quantitative, from third party sources as well as directly from your target audience/customers.

2. Second, enlist input from trusted experts in your field. Analyst briefings have been enlightening in my experience and documenting their feedback as a source helps reinforce the market perspective.

3. And finally, face the feedback from key executives and stakeholders head-on. I approach this step formally, by sharing a document citing all of the sources above, with review deadlines and comment access. This allows for conflicting feedback from key execs and stakeholders to become clear early.

If necessary, I schedule a meeting to review the comments, specifically the conflicts and settle them live. This way you have input, alignment, and buy-in (or at a minimum disagree + commit) from the teams you need to have onboard to activate the messaging in the market.

This response is for messaging alignment (not alignment on all marketing activities). 

- Build a comprehensive messaging framework. A good framework captures buyers, pain points, overall positioning, value pillars, differentiators and reasons to believe/proof points etc. Usually a lot of alignment can be gained by simply agreeing on the assumptions

I often find confusion and misalignment is on the altitude of messaging that execs are expecting. Some execs expect a more feature centric messaging ,while some insist on value outcomes. Some want to hear the "What does your product do" while others want to see a "Why is this different" while others insist on competitive differentiators. A good messaging framework captures these nuances well, and also the assumptions behind it. You can talk about what you will lead with on your website, vs. your pitch decks, vs a conversation with a "low intent prospect'. By explaining the different channels where the messaging will be applied, you will be able to gain more alignment

- Customer validation - Any new value prop, messaging refresh, strategic narrative etc. should be validated with customers before you release it. Customer research is different from customer validation. Customer research is done before you build your messaging to understand their pain points, value outcomes etc. Customer validation is asking for feedback on your messaging once you have developed it (e.g. walk them through your refreshed pitch deck and ask them if it resonated with them and why). Those customer interviews will make your messaging exercise better but also help you gain alignment with execs 

- Brand tone and voice - I personally find a lot of exec discomfort with messaging is less to do with the substance of the messaging but more to do with its adherence to company brand tone and voice. This is especially true for smaller companies which don't have a formal brand playbook defined and a lot of feedback is around "this doesn't speak to our brand" comes from the founders/CEO/early execs. Instead of challenging that thinking, work with them to understand what speaks to their brand. Engaging professional copywriters can help

- Message testing and A/B testing - The ultimate test of messaging comes from its applicability in the field. If there are philosophical disgareements on what your story arc should be, why don't you just A/B test it out. ? Create two pitch decks with two different story flows and see which one lands better with prospects. Or run copy test on your website and see which headlines lead to higher conversion rates. Tools like Wynter also help conduct scientific message tests at scale.

To align executives and stakeholders, and receive their buy-in, you have to tell them where your brand is going before you say how to get there.

Concerning your question, you need a solid Communication Strategy, which is made of two parts:

• Copy Strategy and
• Media Strategy.

The former states, in strategic terms, what Benefit your brand offers, the Reason Why the benefit is what customers want, and the Acceptance of customers of your copy strategy.

The latter details how to bring the copy to the target (customers).

Given that marketing without numbers is just fiction, every strategic statement is backed up with solid evidence, mainly from marketing research studies.

It is the strategy formulation that may make the difference. If you have a chance to see how P&G brand teams formulate strategies you will immediately realize that strong strategies are short and to the point: One quarter of a page for the strategic statement and 1-2 pages of supporting evidence.

These documents guide the execution of communication activities and make sure your activities contribute to reaching the overall marketing objective. There is no room for I-Thinkers in strategy.

Good luck