[ohwello]

It's my impression that gross profit includes marginal costs, but not overhead.

I can't speak for the author, but every SaaS company I have been involved with had marginal costs such as customer support. When you are a tiny company and these tasks are performed by founders you could perhaps roll these costs into overhead and claim 100% gross profit. But as a growing company it would become clear that you need to hire someone for every X customers.

[logicallee]

But selling you a nail for $1 also has some potential support costs - so is it wrong to say that if I buy a nail for $0.25 and sell it to you for $1.00 that has gross profit of $0.75?

But the average customer's support costs might be more than $0.75 -- so would you say that by buying for $0.25 and selling for $1.00 to you, it's actually a loss leader? (I'm really trying to get you to buy more expensive products from me)?

Overall I would like confirmation if this is really what is meant. It doesn't seem to me that support costs would be taken out of gross profit - that is what I think would be taken out of net profits. . .

But I'm sure accountants have well-defined rules on this so I would like to heir their take.