[gnramires]

It's not always possible to design avoiding precision components though (although as you mentioned trim components could fit the bill). If you want to precisely measure current with a shunt resistor for example, you need high precision (although you can also calibrate it digitally). More than precision, which can sometimes be calibrated against, there are also various kinds of environmental stabilities that may be more important: temperature stability, pressure stability, etc. -- you'd need other forms of calibration, measurement and compensation.

Also, component-level precision has limits because eventually trace impedance starts to be significant (hence the use of trim components you mentioned!).

Youtuber Marco Reps goes through various high precision equipment that often have precision resistors and such, recommended if interested!