Motivation is a funny thing. I'm not great at finding motivation to actually work on my projects. But when it comes to doing professional work on e.g Hazel I have no trouble staying motivated.

Lately I've started wondering why that is, could it be because I have a monetary incentive to work on Hazel? Is it because Hazel is a large project? Am I just lazy?
Well, I think it might be a combination of all of the above.

We're a Team

I think one of the primary reasons why I'm able to stay motivated when working on Hazel is because, well, it's not just me working on it. There's a whole team working on it, and that team is depending on me to finish whatever work I'm doing, and they're depending on me finishing it within a certain time limit (Even though we don't really have deadlines in the same way that other companies do).
This of course means that I have a responsibility to actually finish my work, which in turn helps me stay motivated.
Naturally working in a team comes with its own battles, not everyone on the team will agree with eachother on everything, and being in a team means that communication becomes far more critical.

Bigger Project, Smaller Scope

Hazel is a much larger project than any of my personal projects, so you might think it'd be harder to work on since it's a more complex scope. But I've found that it's often easier for me to work on Hazel because the scope of the things I work on is far smaller since I don't have to work on the entire engine, instead I'm focusing in on a small number of systems.
Now, unlike many larger teams we do have to work on multiple larger systems each, for an example I'm responsible for writing and maintaining the physics engine, the C# scripting engine, and doing general maintenance, I've also recently been in charge of managing the Linux port of Hazel.
But that's still a smaller scope than developing an entire engine single handedly. And because of that its easier for me to stay motivated when working on Hazel.

The Monetary Incentive

And of course, we have to talk about the monetary incentive. I get paid to work on Hazel, I don't get paid to work on my personal projects.
Now, I definitely don't think that money is a requirement for staying motivated, but it can definitely help if you're being paid. Of course it can go the other way as well, sometimes you might lose motivation for something when it becomes a job.
That isn't the case for me personally though, getting to work on Hazel every day, and getting paid to do so has really helped me gain motivation to sit down, and just work.
There's a rather well-known quote that I'm sure you've heard at least once in your life: Choose a job you love and you'll never have to work a day in your life
Personally I think this quote is complete garbage. Of course I'm not saying having a job you love is a bad thing, it isn't, if you truly love your job you're bound to be a lot happier.
But it's still work, and that's a good thing in my opinion. Beeing able to draw a clear line between personal life and work is critical to live a healthy life.
Naturally everyone should strive to find a job that they want to have, but for a lot of people working with something that they previously had as a hobby turned out horribly, because they start to view it as work, and frequently they don't enjoy it as much.
While I still very much love my job, and I absolutely love software engineering in general, I think doing it professionally is affecting my motvation to work on personal projects. Because to me it's no longer just a hobby, it's job 9 to 5 job.
In my case I'd still consider working on Hazel professionally as a step up, and I'm really glad that I got the opportunity to do so.

Over Scoping

I have a horrible tendency to over scope my projects. But I'd argue it's for good reason, I'm passionate about working on game engines, and game engines are generally speaking large in terms of scope.
But I have this horrible tendency to try and work on everything all at once, and then I get overwhelmed and I stop working on it.

Anyway, that's all I've got for today, just decided to do some rambling here because I was feeling very unmotivated to actually work. Anyway I'm planning to talk about some other stuff eventually. Thanks for reading!