And this is where BJ Fogg’s behavioral model of behaviour=motivation x ability x trigger comes in. Even with high motivation, action is less likely to occur without high 'ability' also being present (this would be the 'environment' piece James talks about here).
Obviously if your 'environment' makes the desired action too difficult to do, you can’t really do it with motivation alone!
You increase ‘Ability’ by placing 'signal' triggers to remind/prompt you to take action, or making the action appear easier to yourself with facilitators' e.g. packing your gym outfit the night before so it’s easier to then go to the gym, or placing a bottle of water next to your desk to encourage you to drink more water.
Essentially, if you’re motivated enough to do something you can make it easier by also finding ways to identify friction and strains on your resources (time/money/effort) and figuring out ways to remove those friction points.