LDD has been around a while. You could build with a reasonable selection of bricks in a reasonable selection of colours, and then order your models.
That’s all fine and dandy and delightfully entertaining, but when you’ve been bursting with ideas for Lego sets your entire life, the selection of bricks (let alone colours of bricks) eventually becomes somewhat limited.
So you pine for something more. Imagine a suite of almost all bricks ever made, and the ability to paint them in any available colour…
Imagine no more.