What do users think about the product? 

Is it useful and valuable?
Do they find it credible?

Promoting a clear, primary purpose, supporting the "Why" behind the experience. Focused on the benefit – while aligning with top tasks.

Every facet of an experience should strive to promote a single, clear purpose, to support its reason for being.

The purpose should be driven by the underlying goal(s) of the end user, supporting any associative business goals, while providing clarity of information and affordance.

Tailored to unique experiences.

User behavior should be used to inform a contextual experience that is tailored to one's goals; yielding levels of hyper-personalization.

A personalized experience should surface the most relevant and contextual information and anticipatory actions for the end user. The end user should hold a refined level of awareness around the experience being tailored to them; should be implied, but not necessarily specified.

Validate and verify with insights.

All experiences should be supported by research, and validated and verified via a combination of insights sources; qualitative and quantitative, in combination with such things as established patterns, interaction design, psychological principles, etc. – to an extent that yields confidence and mitigates risk.

Nothing worse than a solution in search of a problem – Start with the problem, not a solution.

It is easy to get excited and distracted by new technologies; however, as solutions are explored, don't start with the technology you wish to leverage, start with the problem. As you research, analyze, and ideate, you will naturally gravitate towards solutions that are most fitting to solve the problem you originally sought out to combat.

People look to the behavior of others to guide their actions and decisions.

This can take many forms; including, but not limited to: ratings and reviews, testimonials, validation logos (through brand association), and user generated content.

Be mindful of persuasive design mechanisms (like scarcity or fear of loss tactics) and be respectful in their implementations.

Don't trick people with Dark Patterns – tricks used in websites and apps that make people do things that they didn't mean to do, like buying, downloading/installing, or signing up for something; which is further compounded if the designed experience targets those that may lack technical aptitude or experience (like children).

Be conscious of implementing more addictive interaction design patterns, such as infinite scrolling. An experience can and should be engaging, but it should also be humane.