Cost of change ---> one of the key reasons a customer won't move ahead with your solution is because the cost of change is too much, (i.e how hard it is to implement, to learn your system, use it, train the team) and a big part of that comes down to your demo.
The more non-relevant features you show that aren't tied to a specific challenge the customer has, is just pushing your solution further and further into the too hard, not relevant basket
Here is one way to see if your demo is problem solving or feature dumping and you can actually do this in a live demo, not just for prep.
Are you able to use the tool https://blank.page/ to create an empty tab before each feature you show, summarising the customers challenge you're solving?
This will help you only show what's relevant & problem solve vs feature dump, but also help your customer understand your product better & reduce overload during the demo by seeing the one line summary first.
Keen to see if this works for anyone!?
I made a 10 second video on this below to show.
https://lnkd.in/eAMXHupu?