Value-based pricing means setting your fee against the outcome the work produces for the client, not the hours it takes you to do it. If a piece of work is worth $100,000 to the client and you can do it in a day because you've done it forty times, you charge against the $100,000, not the day.
It only works when two things are true. First, the outcome is measurable enough that both sides can agree on roughly what it's worth. Second, you have enough proof — case studies, references, prior work — that the client trusts you can actually produce the outcome. Without those, value pricing turns into an awkward negotiation and you end up back at hourly anyway.
The honest trade-off: value pricing rewards experience and pattern-matching, and it punishes anyone trying to learn on the client's dime. I keep a senior delivery rate ($275/hr) for scoped work where hours are the right unit, and I price advisory and outcome-shaped engagements separately. Same person, different unit of value, deliberate split.