KiCad's library footprints are silently wrong often enough that hobbyists who trust them without manual datasheet verification get boards back from fab with components that physically don't fit

KiCad ships with roughly 20,000 component footprints maintained by community volunteers. Many of these footprints are generated by automated scripts from generic IPC-7351 rules rather than from manufacturer-specific recommended land patterns. The result is that a non-trivial percentage of footprints have pad dimensions, pin spacings, or pin numbering that don't match the actual component. A classic example: the 78xx and 79xx voltage regulator families look physically identical (TO-220 package) but have completely different pinouts, and KiCad's library has historically conflated them. When a hobbyist lays out a board trusting the library footprint, orders 5 PCBs from JLCPCB ($2), waits 1-2 weeks for shipping, and then discovers the IC doesn't physically seat on the pads or that Pin 1 is wired to the wrong net, the board is scrap. The cost isn't just the $2 in PCBs — it's the $5-15 in components already soldered or ordered, the 2-3 weeks of wasted calendar time, and the momentum-killing frustration that causes many hobbyists to shelve projects permanently. For small hardware startups doing their first custom board, a footprint mismatch means a complete board respin with another 2-3 week cycle, potentially missing a crowdfunding deadline or demo date. The problem compounds because the failure mode is silent: ERC and DRC checks pass because the schematic symbol and footprint are internally consistent — they're just wrong relative to the real-world component. This problem persists because KiCad's library contribution model relies on unpaid volunteers submitting footprints without mandatory verification against physical components. There is no automated system that cross-references KiCad footprints against manufacturer-published dimensional drawings at scale. Third-party verification services like SnapEDA and Ultra Librarian exist but add friction (separate download, import, format conversion) and have their own accuracy issues. The KiCad project warns users to 'treat every downloaded part as untrustworthy,' but this shifts the burden onto hobbyists who lack the experience to know what to check.