No, I am not really building a house. This is a story about many houses (websites) are build these days.

The building #

You are a group of developers and get the task to build a house. You have done this before multiple times, you check the acceptance criteria and start building; you build the base, walls and the roof. After that, you paint the house like requested.

The issue #

The house looks gorgeous, all acceptance criteria are fulfilled. You applaud each other and move on to building another house.

Suddenly, a call from the manager: The customer is not at all happy with the house. There is no door, they can't get in the house. Is this a bug or a feature, you wonder. According to the acceptance criteria, the house should have no door, so this will be handled as a feature request.

So, you demolish part of the wall and add a door. The customer likes the new door. You applaud each other and move on to building another house.

Wait, another call from the customer: They also say they miss windows. The calls, building, applauding continues for some more month. At the end, it cost ten times more, took 8 months longer; nobody is applauding anymore.

Before not after #

This could all have been avoided by planing it right from the beginning.

It has been said thousands of time; Plan for accessibility and performance before you start building. Sure, you can fix accessibility issues and improve performance after you build, but it will take way longer.

Think, think some more, start building.