Those hardware store taps are awful.. Carbon Steel, instead of HSS, not even ground.. But sometimes you have to get by.. I am lucky, Travers Tool is 4 miles away.
Amazing how long good taps will last.. Sadly, last week, I broke one of my favorite 1/4-20 taps, after using it for years... I think it was an Emuge brand.. Not cheap, but really a bargain, if you consider how many holes it tapped..