Here's an old sales joke:
What are the three most important things in real estate? Location, location, location.
Here's my updated version for the web:
What are the three most important things in a website? Performance, performance, performance.
I love beautiful fonts, photography and animations as much as anyone who works in a creative agency, but if it increases your site's load time, you might want to scale back.
Steve Lohr for NYT, For Impatient Web Users, an Eye Blink Is Just Too Long to Wait
People will visit a Web site less often if it is slower than a close competitor by more than 250 milliseconds (a millisecond is a thousandth of a second).
“Two hundred fifty milliseconds, either slower or faster, is close to the magic number now for competitive advantage on the Web,” said Harry Shum, a computer scientist and speed specialist at Microsoft.
The performance of Web sites varies, and so do user expectations. A person will be more patient waiting for a video clip to load than for a search result. And Web sites constantly face trade-offs between visual richness and snappy response times. As entertainment and news sites, like The New York Times Web site, offer more video clips and interactive graphics, that can slow things down.
But speed matters in every context, research shows. Four out of five online users will click away if a video stalls while loading.