Came here to say this, although in a slightly different way. No matter what your bill rate is, if your commit is for xx hours per week/month, you're always going to feel like you're losing. Especially when you _inevitably_ encounter the customer who gets irate when you could only manage yy hours of brainpower in a week, even if those hours were superhumanly productive (and they probably were, amirite, or you wouldn't have burned out early for the week). In an age where so many people are seeing past the lie of butts in seats for 40 hours a week, don't be the one to subject your own self to the same.

this is a very good point. It's like handling dynamite but for an individual or very small team fixed bid is the only way to real revenue.

Think of it this way, you have 40 hours * sizeof(yourteam) to sell per week. There's a ceiling on $/hr or you price yourself out of the market and you don't have a time machine to create more hours. You can either add people to the team or detach the price from time with a fixed bid.

If you don't want hundreds, if not thousands, of consultants in your company then fixed bid is your only path forward.