Motivation and long-term practice

Refining right view, right resolve and with it virtue till right lifelihood, is ones right effort. Else comes based on given courses. As what motivates, what drives: Dukkha is cause of Sila, cause of Saddha. Saddha the begin of the supra-worldly path, good householder. This path isn't one for another gain then freedom from suffering.

[OP:] How do you deal with motivation swings on a scale such as this? What can I do to change this pattern and boost my progress? Observing all of this does not seem to have much of an impact, at least so far.

Imho, there's no secret sauce or magic formula to quickly solve the above issue, which is common to most practitioners. Looking from the cosmic perspective of many many rebirths ago, it does seem to make sense afterall: our mind has been operating in such chaotic/swinging mode for so long such that the few recent rebirths where we do get the opportunity to practice in accordance with the Buddha's Teaching simply have not generated sufficient strength to override that ingrained chaotic mode. So, like other poster's note about the "sprint vs. marathon" analogy, there's no secret or shortcut, one just have to keep cultivating the good Path persistently and consistently. And hopefully with sufficient time and effort, the new wholesome training will gain enough strength and stability to take over, dominate, and eventually eradicate the unwholesome one.

When other life matters intrude, those intrusions can actually be taken as excellent opportunities for practice. In those moments of attachment, we can choose to be mindful of the Buddha's teachings. We can choose to let go of desire and aversion for the world.

DN34:1.5.8: A mendicant meditates by observing an aspect of the body—keen, aware, and mindful, rid of desire and aversion for the world.

So instead of hanging on to a hobby success or a work challenge, we can face these attachments squarely and resolutely, thinking, "now is the time to be rid of desire and aversion for the world." Wouldn't that be a practice of mindfulness?

Mindfulness requires appraisal.

DN34:2.3.81: And how does a mendicant have four supports?
DN34:2.3.82: After appraisal, a mendicant uses some things, endures some things, avoids some things, and gets rid of some things.

For example, if we notice that the roof is leaking at the time of meditation, perhaps it would be prudent to use a bucket and put it under the leak before meditation. And if a hobby thought intrudes, perhaps it is best to be rid of that thought before meditating.

"It’s good to remember that we’re not here just running 100-meter dashes. We’re running a marathon, which means you have to learn how to pace yourself. If you push yourself too hard, you won’t finish. If you don’t push yourself hard enough, you won’t finish.

[snip]

Even if you stumble, remember: This is a marathon, you can pick yourself up and keep going. If it were a 100-yard dash, if you stumbled that would be the end of it, you wouldn’t even try to finish. But in this case. you do pick yourself up, dust yourself off, and keep on running."

~ Thanissaro Bhikkhu "How to Push Yourself" https://www.dhammatalks.org/Archive/Writings/CrossIndexed/Published/Shorttalks/120403(short)_How_to_Push_Yourself.pdf

So you notice cycles in your practice? Like you keep seeing the same pattern repeated over and over again? Dare I say, its almost like a spinning wheel rolling and rolling ever onward almost under its own power?

You're trapped in a karmic cycle, buddy. You keep falling for the same bait. That buzz that you get at those high times? They will invariable burn themselves out. They always do. And they will always be followed by those lulls where your motivation wanes and you can't muster the energy for practice. Stop falling into that trap!

Practice has its highs, but it's not the heady high of new love or a new interest. Real practice should be like a stroll. We can't let ourselves go stagnant. If we do, we'll never make any progress. But we can't sprint either. If we do, we lose our wind and find ourselves stopping long before our destination.

If I had any advice to give, it'd be to stop reading, stop trying to motivate yourself, and stop trying to create those periods of intensity. All they're doing is leaving you thirsty when they invariably dry up. Instead, make your practice completely ordinary - like brushing your teeth in the morning. Brushing your teeth isn't terribly exciting. I mean, no one goes through spurts where they get a buzz just thinking about fluoride and bristles. Assuming your teeth haven't already fallen out, it's probably just an ingrained pattern in your life. You probably don't give it much thought. Wake up, take a pee, brush your teeth. It's automatic because you've accumulated so many uneventful repetitions since the time you were old enough to reach the tube of toothpaste in your parents' bathroom. Let your practice be just another form of hygiene. Stop trying to make it special.