Scalability is a requirement from the first architectural decision, or it's a problem you inherit later. Once a system is built without it in mind, there's no clean way in. You can't retrofit scale onto a foundation that was never designed to carry it. The only option is to patch around the cracks until the patches become the architecture.
We at W2S Solutions understand that. The enterprises we work with run applications and infrastructure where slowing down isn't an option. So we design for the load they don't have yet, from day one, because that's the only point where scalability is actually possible to build in.