An accurate extruder rotational distance tuned for your specific extruder head is critical, if off so will all of Klippers extrusion calculations. This should be done before other tuning and calibrations relating to extruding filament.

Ellis's Tuning Guide provides a good explanation and covers the canonical process for tuning the value. See https://ellis3dp.com/Print-Tuning-Guide/articles/extruder_calibration.html

The best video resource for demonstrating this process is 00:02:22 into this YouTube video by Wild Rose Builds.