If you set goals and you want to achieve those goals or execute it, personal development is important for you.

If you want to develop new skills and knowledge through learning and training, personal development is important for you.

If you want to build self-awareness and self reflection through introspection and feedback personal development is important for you.

If you want to enhance emotional intelligence, communication skills and social skills, personal development is important for you.

If you want to practice self-care such as exercise, meditation and mindfulness personal development is important for you.

Books to read on personal development

- The 7 habits of Highly effective people by Stephen R. Covey

- Mindset: The New Psychology of Success by Carol S. Dweck

- The power of Now by Eckhart Tolle

- The Alchemist by Paulo Coelho

- Atomic habits: An Easy & Proven Way to Build Good Habits and Break Bad Ones by James clear

You can Read Books on Amazon, Bambooks, Oodles, KoboBooks, Wattpad, Goodreads etc

Apps you can get courses and invest in your self: edX learning app, Alison, Coursera, Khan academy, Udemy etc