A problem statement is the sentence you will spend money on. If it is vague, the ads will be vague. If you cannot say it out loud, you do not have it yet.
Talk, then edit
Describe who hurts, what they try today, and why that fails. Microphone drafts the problem statement and the hypotheses. You cut anything that sounds like a pitch.
Turn it into a test
Each hypothesis should name an audience and a claim you can put in an ad. If you cannot buy a click against it, it is still a diary entry.
Then research the market
Microphone also drafts market research from the same conversation — who else sells a fix, and where those people already gather. Use that to pick the first channel, not to write a report.