Ive seen many people train to absolute failure during their last set.
Failure is does not mean the same thing to all people, not at all. Everyone claims to
train to failure, and it may seem like they do. But training to failure in an HIT context
also means you are also trying to hit higher poundage or increase the reps each and every workout.
Most people are not trying to get stronger all the time and don't even try. But if you pressure yourself to do it it becomes a whole different thing very quickly. When you think you have one
single set to stimulate growth for that particular muscle each week it makes you pull out all the stops which most trainees do not do.
You can try it yourself. Take your best ever 8 rep max on say squats. Then next session you WILL beat it, and next after that and so on. You have been thinking about that set each week, it's life or death, you load up on tons of stimulants and oral steroids before hand and then get to work.

Before long you will notice the difference between "failure" and Dorian/Mentzer type failure. Most people do not tap into those extra reserves because it is enormously taxing despite the low volume. I will give another example. A powerlifter does 9 singles max in a meet but every powerlifter will tell you how taxing a meet is, for some it may take months to recover from it. Why, it's only 9 singles? Because when your whole months/years build-up to that point is on the line you will give it much more than an average "workout" session, the average dude in the gym trying a few maxes simply does not extend himelf as far.
Try the squat example. Try it for a few weeks. You MUST beat each squat session in either poundage or reps... do one or two sets a week... see how it goes.
