Yeah, building a cabin isn't a fundamentally complicated project. Think. Measure. Measure. Cut. Nail. Repeat.
On a serious note, there's so many similarities between building a house and a web app.
Without a proper plan and a blueprint, preferably by an architect and not the contractor - forget about it. Client never knows what they want. Small changes (KILL ME NOW) can take huge amount of time and impact things that don't seem connected, which the client never understands. The last 10% is rarely completed or done badly. It always takes much longer than expected. Everyone's excited in the beginning and considers euthanasia toward the end.
It's hilarious really.
Maybe my crap's not loosely coupled enough.