I was accepted into the NOHA programme. They specifically asked why I wanted to join the programme so my motivation focused on (1) my background (a very short against all odds story as the introduction) and how that influenced my career path. More of the text centred on (2) my career path i.e. What I have done so far, what I would like to do in the future and how the programme would help me achieve that. Lastly, I wrote a bit about (3) My country/region and how badly in need it is of people with the specific skills the programme promises to teach.
I think my motivation was quite personal. I told a story and painted a picture about my life , where I am going and why the programme is a perfect fit so that whoever read it would see strong intent.
At Masters level they didn't ask for a specific project but I did have one or two lines in my motivation explaining my research interests. I didn't go into detail.
About academics, I did mention that I graduated top in my class but nothing else. I contacted my past lecturers before submission and asked them to focus the letters on my academic achievements.
Each programme has different requirements but I think lecturers like seeing purpose. Make sure your purpose is clear.