Books like Daring Greatly
Brené Brown
Daring Greatly is 287 pages, about 5 hours 16 minutes at 250 words a minute.
6 books to read next
How long each takes
Don't Say Yes When You Want to Say No 5.3 h 
When I Say No, I Feel Guilty 5.9 h 
The Assertiveness Workbook 3.8 h 
Asserting Yourself 4.5 h 
The Complete Idiot's Guide to Assertiveness 6.2 h 
The Anatomy of Courage 3.9 h Bar height shows length. Estimated at 250 words a minute.