What tactics have actually helped you get customers to adopt the product when momentum slows?
The most successful way to gain momentum and create a sense of urgency for product adoption is to tie it to an immediate business need or strategic initiative for the client. Here are a couple of tactics I find helpful:
Repurpose a weekly or monthly touchpoint with the client and use it to discuss their initiatives
Identify a specific high impact pain point they're having and align your product as the solution
Provide examples of how other clients have successfully used the product
Expand to other teams within the clients organization and determine how they can benefit from your product
This is going to depend heavily on your product.
In our case, customers use our product to improve the way they work, so we have dozens or hundreds of users in a given account with high consistency role to role, and we have centralized administrator(s). That means we can talk to a few people to move the needle on the many.
We do a few things:
Talk to someone! Start with the champion or the exec who purchased the product to understand if their needs are changing, if we should push on a different use case, or what makes the "good" users different from the "not so good" users. Refresh your success plan and move forward.
Roadmap as Bait: Many disengaged customers will show up for an exclusive peek at the roadmap. Offer a roadmap preview as a way to get the customer on the phone to check in on their priorities, and to get them excited for what's to come. If you don't have a customer-facing roadmap slide, insist on having one made.
Benchmark: Show your customers how they stack up against their peers. Our best customers are achieving X, you are way below... let's talk about how to get you there. You can do this at scale or in a conversation.
Engage users directly: You have to get the content right. Personalize according to roles and use cases that are likely important to them and push content directly through in-app, webinars/events, emails <- whatever works for your users. Always give them 2-3 easy things they can start doing in your app immediately and have big payoff.
The bold move: Send an adoption report to your exec buyer or champion. This highlights top users, what parts of the product they are/aren't using, and who is not using (Note: this is risky if you have a renewal coming up so experiment before going big.)