Let us, for a moment take a step back and discuss why we want to scale applications. The main reason is high availability. Why do we want high availability? We want it because we want our business to be available under any load. The bigger the load, the better (unless you are under DDoS). It means that our business is booming. With high availability our users are happy. We all want speed, and many of us simply leave the site if it takes too long to load. We want to avoid having outages because every minute our business is not operational can be translated into a money loss. What would you do if an online store is not available? Probably go to another. Maybe not the first time, maybe not the second, but, sooner or later, you would get fed up and switch it for another. We are used to everything being fast and responsive, and there are so many alternatives that we do not think twice before trying something...
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