I've heard this phrase for a while but it wasn't really until this year that I'd better grasped what it meant.
In order to perform our best, we, as riders (or drivers) need to be working toward using the right controls at the right time, hitting our markers, and working close to the limits of adhesion of the tires. Very seldom do the vast majority of riders do this and most of us don't have a good feel for those limits. There are plenty of riders we see for a track season or two who often find and cross those limits and often don't return for another season, whether it's by choice or not.
Between 2018 and the end of 2021, I'd completed roughly 100 track days, the vast majority on either my Daytona 675 or the Daytona 765. I've known since I started working on my riding that I was nowhere close to the limits of the bike but for a risk-averse person like me, it's scary to try to find those limits, especially not knowing what they feel like. My reason for selecting and preparing the bikes the way I did was that I wanted to have something that was very capable and I wouldn't need to upgrade. I think a lot of us go into this sport and immediately think that we need to upgrade components even though they're not bad out of the box. There are some things that I know I personally prefer (I really like the feel of the Brembo RCS Corsa Corta brake lever) and do upgrade those parts or if there is a known problem area on a bike (stock brake rotor on a Ninja 400), those are worth upgrading.
Early 2022 I decided to try an experiment, spurred on by Ken Hill and seeing so many other competent riders/racers having fun on them, and that was to get a Ninja 400. I deliberately upgraded only the necessary or weak bits, namely the front brake rotor, brake line, and pads, and installed track fairings and engine protection bits, shifting and clutch fortification, and a few other small things. With this bike I'm starting to find limits, namely in a collapsed front-end under hard braking and some occasional front and rear tire slip (albeit slight). At the kart track, I was able to drift the bike a bit just in lean angle (not braking or acceleration). I'm starting to find some of the limits of this bike.
Now, when I ride my proper track bike, the Daytona 765, I feel safer exploring further than I had before. I've also become aware of a couple more things in how my riding is changing: 1.) while my brake markers for the N4 are fairly defined, I'm often using those with the Daytona (I'm not braking at my same relative position to the markers, but when I see the N4's markers in the distance); 2.) my lines are altering slightly--I'm starting to use a more 'flow-y' type of riding to link corners. For example, I'm thinking of Sonoma T9-T10. In the past on the Daytona, this used to be more sectional--I'd come out of T9 as hard as I could in 2nd gear, catch 3rd while upright, then tip in for T10. I could see the breaks in the riding in chase video. I haven't had chase video in my last couple of outings but I'm feeling it more as tighter links in my riding. Part of it is that this last time at Sonoma I used higher gearing around much of the track, which allows me to get back to WOT sooner. The higher gear selection also seems to be allowing me to carry more roll speed in the important bits.
The first 6 or so track days this season I was without the Daytona and I'd gotten used to riding the N4. My first outing on the Daytona after that was terrifying and I was beginning to think the N4 had broken my ability to ride the Daytona. The next outing on the Daytona though and things started to click for me, and click better. I've seen appreciable improvement in pace at all the tracks I've ridden this year on the Daytona now. I am beginning to appreciate what the N4 has done for me. I still feel like I've got a lot more to go with the Daytona with some of the skills the N4 has helped me build. It's a good reminder that in order to move forward, sometimes we may need to fall back a little, digest, and move past where we were once before.
I remember my first big plateau at Sonoma a couple of years ago. I'd gotten to a point where I was consistent in lines and direction but I couldn't get any faster because the bike would feel unsettled. It wasn't until a marginally faster rider passed me on the way into T6 and I was able to keep him in sight for nearly a lap. I came to realize that the his bike was moving around, skipping over some of the numerous bumps, and since the rider's technique was valid, I realized that to go faster, I would have to learn to accept that the bike might be moving around a bit due to the track's worts. Once I came to terms with that, I was able to shed several seconds. My last outing at Sonoma, I worked on carrying more roll speed. In that I hit 101.5 mph out of T5 on the way into T6. At that speed, the rear wheel actually pops up off the ground momentarily but that's part of what it takes to go fast there. Exiting T2, you run out toward the left as you work your way back to the right for T3. If your rear wheel isn't skipping due to the tar snakes and bumps, you're probably not accelerating as much as you can. I've re-watched the MotoAmerica super sport races at Sonoma many times and each time I watch I find different things where I know I can work up to.
https://www.youtube.com/watch?v=IuGT1jsaYTI
Now that I'm able to find and feel some of the limits on a far less capable bike, I'm less afraid to push myself further with a proper bike as the sensations/feelings are the same but they'll be happening at a higher level and if I'm not getting those sensations, I'm not there. It's not something I'll jump to on every corner every lap, but I can build my pace bit by bit until I start to feel those sensations. Riding to the bike, if it's too far ahead of you is tricky, particularly if you don't have a sense of what the limits will feel like. If I could go back 3 or so years in time, I would have started with something like the Ninja 400 and started building feel for those sensations that way. Good luck telling me at that time though.