Some metrics make you feel good but are not meaningful, these are called vanity metrics.
Besides being useless, they might sometimes paint the wrong picture and become harmful when decisions are made upon these.
Reference
Ries, Eric. The Lean Startup: How Today’s Entrepreneurs Use Continuous Innovation to Create Radically Successful Businesses. 1st ed, Crown Business, 2011.
Highlights or timestamps
many startups give in to the temptation of using vanity metrics, flattering but useless or even harmful metrics that make a company look good but don’t help bring it closer to its goals.
— ^ecf005 from The Lean Startup
Other vanity metrics could be the hours of work you’ve already put into a product or the number of milestones you’ve accomplished.
— ^2effa6 from The Lean Startup