Do you even measure?
It hasn't been that long for baristas to measure the coffee extractions. If you remember the cafes back in the 2000's, most of the cafes were using manual grinders. Most of them were not using a scale to measure how many grams they were dosing and were extracting. Rather than the 'gram', many baristas focused on 'extraction time'. We used to think that espresso is a coffee that is brewed with 14g of coffee, extracting 30ml in 24-28 seconds. If the shot was extracted faster or slower, that shot was not used to make drinks. Back then, it was really important for baristas to be able to dose the coffee as a similar amount as possible because the extraction time is dramatically changed if the barista's skill is inconsistent. Maybe that's why the old school baristas were very sensitive.
As developments in barista technics and equipment are enhanced, people started using scales, refractometers, etc. to measure their coffees in various ways. And now, most specialty coffee roasters and baristas including barista competition participants are measuring as many variables as possible. For example, we measure moisture content, density, water activity for green coffee, weight, development time ratio, time, rate of rise, total dissolved solids as a brewed coffee, extraction yield as a brewed coffee for roasting, and various extraction parameters for baristas.
Measurement is a significant thing in everyone in the coffee supply chain. This is because, without measurement, we cannot assure the quality of the coffee as a product, and the quality of the coffee as a drink. Without measurement, consistency becomes worse hence the quality gradually drops down.
So, what should we measure?
If you're a barista or home-barista, it is recommended to measure the following.
Dose(How many grams of coffee you use)
Yield(Espresso; How many grams of beverage yield you extract)
Yield(Pourover Filter; How many grams of water you pour)
Temperature of Water
Also, it is important to use a micro-scale that can measure and show 0.0g.