Ivanofski,
your 98% may be true for the basic training, even though I think it is a high number for that as well.
However, I have started training almost 5 years ago (and happily qualified for about 1,5 years, yay) and I can tell you that of all the people who started basic training, quite a bit LESS than 50% have made it to fully licensed ATCO.
My ab-initio course started with 8 people, there's 3 of us left, all licensed.
There was a big group (over 15 people) of which just over half made it out of basic training.
So you shouldn't take any of these numbers as trying to be discouraging, but more as a realistic way of how things happen.
In any case, if you have what it takes to do the job and you dedicate yourself to the training, you will most likely make it. Almost everybody is going to try their best to help you get to the end of your training, but you'll still be the one who has to put in the (huge) effort.