Barry Boehm has been writing books on the software development process for a long time; he is a very smart guy.   I picked up this book back in the 80s.

The graph on the cover describes the improvement in efficiency you can get by improving different aspects of your project.    Some of the improvements are things like better tools and faster computers.  But if you can squint at the fair-use thumbnail I have copied above, you can see that the bottom bar is almost a big as all the other bars combined.  This is the effect of motivation of the software engineers.  Unfortunately, the book only has a few paragraphs on the subject, then goes back to more "scientific' issues.

Did you read the page on universal laws?   What is the most complicated part of a software development project?  The people, of course!   People have goals, dreams, desires, hangups from childhood traumas, anger from past failures. prejudices, distraction from spring fever,  troubled relationships and more subconscious thoughts than anyone has been able to model.  Of course, this is your real challenge, if you want to achieve success in your projects.  This is why leadership is important.

One of the core components of the Agile school is the self-directed teams.  System theory has oscillated back and forth on whether centralized or distributed systems work best.  I assume the answer is "both" in some balance. But I think most developers feel a lack of control over their projects.  The sales people, Finance, Marketing and the executives all have more power, but sometimes they don't understand the project very well.  I think one of Agile's greatest successes is extra motivation it gives to the developers.  If Boehm's graph is correct, that may be the best thing there is.