Why this is a mistake: If you don’t understand your characters’ motivations, the characters will inevitably become cardboard cutouts
to the reader, there only to enact the author’s desire to make the plot work.
Readers want to empathize with the characters, and they have a hard time doing that with characters they don’t believe in. When characters
act out of character, readers just can’t believe in them.
The solution: Before you begin writing, make sure you understand your characters’ motivations, particularly each character’s primary motivator. Once these are locked into place, you no longer control your characters. They are going to act and react like real people. Sometimes they may surprise even you, the author, with their actions.
Remember that your characters are not on Maslow’s fifth level of self-actualization; they have their own blind spots and subconscious motivations. Sometimes even your characters are not consciously aware why they are doing what they are doing. While they might consciously put forth one reason for their actions, subconsciously they have a different reason. This underlying reason usually boils to the surface as the conflict in the story escalates, making for more conflict and drama.