What increases theta?

Could you please elaborate on the factors that contribute to an increase in theta? I'm particularly interested in understanding the variables that might directly or indirectly affect its value. Could market fluctuations, technological advancements, or regulatory changes be among these factors? Also, how do these changes typically manifest in the theta market and how do investors react to them? I'm looking for a comprehensive yet concise explanation that helps me grasp the dynamics behind theta's price movements.