When value pricing wins
The outcome is measurable and dear to the client (revenue, conversions, hours saved), the work is bespoke, and you can articulate the result in their numbers. A landing page that lifts checkout conversion 1% on a $10M store is not worth 12 hours × your rate; it is worth a slice of the delta.
When hourly (or day-rate) wins
The output is process-shaped — maintenance, admin, ongoing advisory — or the client needs predictability more than outcome ownership. There is no shame in hourly done honestly; the shame is hourly done with a rate that ignores the business costs the hourly calculator exists to price.
The hybrid most solo freelancers land on
Projects at fixed prices with buffers; retainers monthly against deliverables; overflow at a published day rate. All three priced from the same floor — target income, real expenses, honest billable time — so switching formats never means switching math.