Business
Unit Economics and Billable Time
Price minus variable cost funds fixed cost. Unbillable hours are a tax on every hour you sell.
A unit is profitable only if price minus variable cost can, in volume, cover fixed cost and still leave a wage you can live on.
Break-even
Fixed cost ÷ contribution margin = units you must sell before the business pays you. Below that line you are funding a hobby.
Billable time
You do not sell 40 hours. You sell the hours left after sales, admin, illness and holidays — then you pay tax and overhead on those hours.
Takeaway
If your desired take-home needs a rate the market will not bear, the model is telling you to cut overhead, raise utilisation, or change the offer — not to ‘hustle harder’.
Run the numbers