Really. It really is. You might hit some speed bumps on this journey and you're entitled to take a break from waist training if you want, for a day or a week or a month or a year or years. Your corsets will be there when you're ready for them. (Of course, it goes without saying that not wearing a corset will slow or undo your progress, but that's a choice you get to make.)
There are all kinds of reasons why one might want a brief respite from their corseting, and all are valid. Remember that you are exclusively in charge of your body and your waist training. Don't let anyone try to tell you there's some "rule" that you have to wear your corset every day, or for a certain number of hours a day, or laced to a certain reduction, or for sleep, or whatever. The only rule in waist training is that you should listen to your body.
Why would you want to take a break? Maybe the weather just isn't conducive to corseting. Personally, I tend to take one to three-ish days off each month in honor of "shark week," although others may find that the compression soothing at that time. As an artist model, there are some days when I'm being paid to wear a non-corseted ensemble, or could wear a corset but it wouldn't be at all comfortable in a required pose. Personal tragedy can also be demotivating, and that's okay, too. Maybe you really just don't feel like it, or you want to wear a certain something and can't work a corset into your ensemble. I've found waist training has increased my body awareness and serves as an excellent barometer for if I'm coming down with a bug: I generally don't feel like wearing my corsets when I'm sick or about to be.
After a break, take the same self attention to easing back into your corseting. Don't push yourself to lace down as long or as tight as you used to if you're not feeling up to it, especially if the break has been for a prolonged period of time. (With a break of just a day or two, there probably won't be any difference.) Even if you've lost or gained a bit of weight, your old corsets will probably still fit owing to the flexibility of the lacing gap (especially if you saved the older ones that are more broken in and have larger waist sizes). Your body is delightfully malleable and you've trained it to be even more elastic, so if you've lost any progress, it'll probably be quicker the second time around.