Yield (first-pass yield)
also: FPY · first-pass yield · rolled throughput yield
The percentage of units that pass each production step, or the whole line, without rework; low yield directly raises cost and signals process problems.
First-pass yield is the share of units that pass a step the first time. Losses compound, so the product of every step's yield (rolled throughput yield) can be much lower than any single step suggests: five steps at 95% each give about 77% overall. Failed units are scrapped or reworked, which costs money and line capacity.
Yield is a key metric from PVT onward. Tracking failures by type and step (a Pareto chart) shows where to focus. Design decisions such as tight tolerances, hard-to-assemble features or marginal circuits often cause yield problems the factory cannot fix on its own.
Founder takeaway
Agree yield targets with your manufacturer, get failure data by step and cause, and treat recurring yield loss as a design question as well as a factory one.
engineer review pending