There was a time, long ago, in a 'fishroom' far away that I was nearly obsessed with testing the water in several tanks. But once tanks are established and you have a routine maintenance schedule (e.g you've figured out the required volume/frequency of necessary partial water changes - testing the water becomes nearly pointless).
The fish and the tank will 'tell' me if there is an issue with water quality.
Now I'm not dissing anyone that regularly tests their water and it can be crucial for newer setups...I'm just confessing that I rarely do it these days. I just know that there will never be results for ammonia and nitrites and there will always be some nitrates... I just don't need colored vials to tell me that. Each to his/her own.