Meaning they decided to procrastinate instead of working on their product/service.
> we instead chose to purchase solid core doors from Home Depot (~$40 each)
Meaning they instead chose to spend more on something that wasn't designed to be a desk than an actual desk.
From [1]:
Ergonomically, door desks leave a lot to be desired. Keyboards were usually too high. Typing for hours could be uncomfortable. And those angle brackets have sharp edges; accidentally scrapping exposed flesh against those was a mistake that wouldn't be repeated.
[1] - http://glinden.blogspot.co.uk/2006/01/early-amazon-door-desk...