In my working experience the ones who came with most qualifications were usually the least competent.
They were good a passing exams, useless in the real world, they never lasted but could undo a lot of good work in their short time.
I went tubeless with the front tyre after a slowish puncture. An instant flat in the back wish I'd done both but only having the one valve is my excuse.
I now have valves ready for when I get around to it.