This isn't about your failure, L., it's about your son's success. Everything you do to help him get trained is really about supporting him. And that includes timing.
Readiness depends on the body (bladder and sphincters) being ready, the nervous system being mature enough to send the right signals at the right time (and this is VERY complex, because there are different sets of signals and sensations before, during, and after peeing), and the emotional maturity to accept the responsibility to drop what the child is doing to go pee. Also, it helps if the child is able to get his own clothing down in time and back on afterward.
Before all these factors are in place, the parent is the one who's trained and on a schedule of regular reminders and enforcement. So a parent who starts training 7 months before her child is ready will essentially be training for 7 months, or even longer if the child has begun to feel like a failure, or frustrated or resentful of mommy's obsession with making him use the potty.
The parents you're comparing yourself to who had an easier time with training had children who were ready in all three essential areas. When that state of readiness is reached, training can happen in only a few days or a couple of weeks.
Going back to diapers creates great dread in many parents who have already invested weeks or months in training. They're afraid they'll undo the progress to date. But really, what if there is no "progress to date" other than your own investment in time and effort? The "failed" kids I've known about who were allowed to go back to diapers didn't get confused. If anything, they got a few extra weeks or months to sort it all out, learn the signals, and become excited about making this great developmental leap forward.
Kids will train when they're ready. For little boys, this may be quite a bit later than girls, occasionally as late as 4 or so. But quite a few show eagerness and interest by the time they are 3. And when they are willing and interested, it will happen very quickly, without bribes, charts, rewards, or punishment. They will be as motivated to use the potty as they were to learn how to walk and talk.
It's good to be aware that poop training involves different signals and happens separately for many children from pee training. Night training is also later for many kids – they sleep deeply enough that they may not notice full bladder signals reliably until they are well into grade school years.