Technical founders have nothing to lose

Technical cofounders have everything to lose.

If you are any good, you have a job and, therefore, the opportunity cost of launching a startup is massive.

This seems a bit naive - perhaps it would be better targeted as "technical founders need less capital".

For instance, you still have legal liability risks, which may vary depending on the problems your startup / business is trying to solve. Especially in the early stage, even if you have a corporate entity wrapped around your startup, mounting a legal defense can be financially crushing. This is doubly true if you are augmenting your cash stream by consulting / contracting.

This may not be very likely, depending on the startup - but to say technical founders have nothing to lose seems a bit naive.

That's clearly not correct, since there is opportunity cost.

I have a deliverable due today; will someone elaborate on the following?

Career Trajectory. Job 1: 5,000 users. Job 2: 10,000 users. Job 3: 500,000 users. Job 4: 1,000,000 users. Job 5: 10,000,000 users. How many users does the startup have, how will that destroy my resume, and how long will it take me to recover my career if the startup fails?

Opportunity Cost vs. Peak Production Years Remaining. I am 20 something years old. I only have so many years of peak production remaining before it's time to have a family and a house and all that. Is a startup the best way to spend those years when I am worth $x per hour on the market?

The basic advice in the article seems to be: use consulting as well as doing a lean startup to achieve (i) a fluid stream of income [from consulting] and (ii) a hopefully-growing stream of passive income [from startup]. (As far as I can tell, it's also what Patrick 'kalzumeus' McKenzie and others are recommending).

Part of the "nothing to lose" assumption seems to be that doing a startup gives you a learning effect that outweighs the lost revenue you had to give up for doing a (failed/failing) startup in the first place?

There's a lot more than opportunity cost. There's the actual money in my pocket lost from the (probably very good) salary that I would be making at an established company. Most people still have to pay the rent or the mortgage. That's the main barrier of entry. It's not that we think we'll have to max out all our credit cards... the cost of renting some EC2 instances pales in comparison to my mortgage, I can tell you that much.