Secret to loyalty: products that evoke emotions.
While using the Moscow or Kano model to prioritize features, PMs invariably lean towards must-haves & basic features.
While this is logical in the short run, starving "delighter" features indefinitely from sprints isn't smart.
Delighters are nice-to-haves that pleasantly surprise users creating positive sentiments.
Without these, the next player with a similar feature set suddenly seems as good as your offering.
There are 2 types of delighters.
e.g. when PowerPoint suggests slide designs when you insert an image or Gmail suggests phrases when typing an email.
e.g. background skins for Trello boards, audio visualization in Winamp, Whatsapp stickers.
These delighters, especially functional ones, can eventually become basic must-haves if you successfully "spoil" your customer's habits.
Ex: Amazon's 1-click checkout started as an exciting feature. Now, it's "yawnable".
When this occurs, it raises the bar on customer expectations favorably towards what your product already supports.
Now, everyone else has to play catch up.
Therefore, identify high-value delighters and protect their priority over time.
They may well be the reason customers choose to stay.