The first question before writing anything.
WHAT TO ESTABLISH
Who will read it What they already know What they need to do What they care about How much time they will give it
WHY THAT LAST ONE MATTERS
It determines length and structure more than anything else.
WHAT CHANGES WITH THE READER
Vocabulary Amount of background What you emphasise What you omit
WHAT AN EXPERT READER NEEDS
Detail, and no explanation of basics.
WHAT A NON-EXPERT READER NEEDS
Context, plain language, and the implication rather than the mechanism.
WHAT A SENIOR READER NEEDS
The conclusion, the decision required, and the risk.
WHY
They read many things and decide quickly.
WHAT A MIXED AUDIENCE REQUIRES
A structure permitting each to read what they need.
WHAT THAT LOOKS LIKE
A summary anyone can read, with detail beneath.
WHAT TO ASK BEFORE WRITING
What do I want them to do after reading this?
WHY THAT QUESTION
It determines everything else.
WHAT TO DO IF YOU CANNOT ANSWER IT
Do not write yet.
WHAT TO AVOID
Writing to demonstrate knowledge Including everything you know Assuming shared context
WHY THAT LAST ONE MATTERS
It is the commonest cause of confusion.