Don't share your book with friends
The day I self-published my book I sent free coupons to 16 close friends. None ever downloaded it. Not a single one.
There are other reasons for not sharing your book with friends, such as not confusing Amazon's also boughts algorithms. But the most important one is not to get discouraged if you're ignored by the people closest to you.
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This is noted but it may not be true when your friends have great admiration for what you do.
In my case the friends do have great admiration for my work, and expressed it when I announced the book. But they still didn't download it.
I would ask for an honest feedback from some to be sure potentials customer won't behave the same way.
Good idea, thanks. Some hinted they were busy and planned to check out the book later, but real life likely got in the way and they eventually forgot.
The point is not seeking product feedback from close people, or at least not immediately, may help control the already high stress of authors at such a critical moment as launching a new book.
I would keep this as experienced advice.