you absolutely have to hold the top thread tail when you start.
That is good information but why don't the techs, repairman, or dealer make a point of saying do that? Is that info in the manual as do that every time? You would think that is a detail that should be told to any machine buyer if it was that crucial. I was taught to hold the thread tail too and many of the newer sewers look at me as being sewing police if I suggest it.