Website Response Times An Article by Jakob Nielsen www.nngroup.com Users really care about speed in interaction design...A snappy user experience beats a glamorous one, for the simple reason that people engage more with a site when they can move freely and focus on the content instead of on their endless wait. 0.1 seconds gives the feeling of instantaneous response. This level of responsiveness is essential to support the feeling of direct manipulation. 1 second keeps the user's flow of thought seamless. 10 seconds keeps the user's attention. A 10-second delay will often make users leave a site immediately. uxperformanceinteraction
What went wrong? If something ships from one of the companies I advise, and it is virtually unusable because of poor design (which as we all know occasionally does happen), you can bet I go directly to the designer and ask how this happened? It is absolutely on the designer to ensure this does not happen, so something went wrong. Similarly, if the product ships and performance is terrible you can bet I go directly to the tech lead with the same question. And most frequently of all, if something ships and the analytics show that it’s either not being bought or not being used, or it turns out that it violates some business constraint like compliance or privacy, you can bet I go right to the product manager with that question. Marty Cagan, Product vs. Feature Teams svpg.com Viability, usablity, feasibility