Why is figuring out how to start one of the hardest parts of writing ?

because you can't decide on just one topic and if you do you can't decide which approach to introduce it you should use. It's complicated because either you have writer's block, you are the exact opposite and think of anything and everything, or you write something down and come up with something better

Starting is far more difficult than improving. The anxiety itself is crippling. The thought that you probably started too late and that you'll never catch up can really put your motivation and enthusiasm to a screeching halt

Explanation/Source: Google

in the thematic approach, an interpreter relies on a central theme (i.e., a major point or message) to guide development of a communication activity or device. in presenting the activity or device, the thematic interpreter develops the theme in such a way that it will be highly relevant to an audience.

explanation: