They're massively inaccurate!!!!
Check if your plant needs watering by pushing your finger 2 inches into the soil, if it comes out dry you need to water!
Depending how dialed in your environment is you could use Relative Humidity as an indicator, this is what i do 55% is my happy place, once it drops to 45% i know ill need to water soon, then when it drops below 40% i defo need to water