Five mistakes teams make with performance budgets

It is rarely the thing that gets a project approved, and often the thing that decides how it goes. These are the ones we run into repeatedly when we audit performance budgets.

Real-world numbers from actual visitors matter more than a score produced on a fast laptop. Doing this properly once is usually cheaper than doing it approximately three times.

The mistakes we see most

• Treating it as a launch task rather than an ongoing one
• Assuming someone else already owns it
• A number in writing stops slow creep
• Budget for total page weight and script size
• Never checking whether the fix actually worked

Enforce it automatically or it gets ignored. The cost of getting this wrong is rarely visible on the day it happens. The practical test is whether someone new to the project could tell, in a minute, that it had been handled.

Making it stick

What this looks like day to day

Performance work is mostly subtraction, which makes it unpopular and effective. Three things worth confirming about performance budgets before you move on:

• Someone can say what the current setup is without going to look
• A number in writing stops slow creep — and you know whether that is true here
• There is a way to tell whether the last change to this helped

Pick the one that would hurt most if it failed, and start there.