Motivation doesn't keep you consistent.
There are a LOT of motivational quotes out here on the interwebs. Really any time you need it, you can find one- sentences, paragraphs, even books chock full of words to inspire. I myself have been moved to change a behavior or take on a task. I'm a huge believer in listening and learning from people who stand for something and are living their truths. I've learned a great deal from people who spend their lives motivating people to live better, feel more, care less.
There is a myth out there that when it comes to fitness, all someone needs is the motivation. They just need to find their inspiration to get moving, to get to the gym, to go for that run. A warm and dry day can be excellent motivation for an outdoor workout. A perfect nights sleep could be the incentive you need to get to that 6am yoga class. Maybe reading an article about the benefits of strength training can get you to the gym after work on that Monday.
But in the end, all of those reasons listed above are external. They came from an outside source, they are conditional- and most often short-lived.
So what does a person need to keep showing up for themselves, for their health? The creation of a routine. Fitting it into your day, your week. Taking the time out to schedule it in like you would for a meeting or for your kids activities. Because there will be plenty of days when motivation will be absent from your life. And when it happens- and you're relying on some incentive to get you moving- the couch will win over the gym, it will be too humid for an outdoor workout, a shitty nights sleep will tell you to skip that class (and realistically, maybe you should- a post for another day).
But. If you have that time already set aside, you will start to show up. And after you continue to show up, you will feel better and better and better. Sooner than later it will become a part of your day, your week- your life. Because you developed the routine and built the discipline to keep going. And that's when it becomes a lifestyle. No motivational quotes needed.