Intelle Brain change that is divided into a sequence of smaller, simpler tasks is less likely to cause stress from uncertainty, fear, or ambiguity and thus increase your chances for success.

Our brains are wired to immediately detect changes or possible errors in the environment and to send strong signals to alert us to anything unusual, or unknown. This error alert mechanism in the brain is closely connected to the brain's fear circuitry. Error detection causes us to act more emotionally and more impulsively.
Our thinking can be easily overwhelmed and flooded with error signals when we are faced with situations of uncertainty, rejection, unfairness, or ambiguity.
To use learning to drive as an example, most of us started slowly someplace where there is little traffic. Our brain was busily making new connections between the parts of the brain that handle vision, motor controls, and making decisions. The increasing level of comfort you felt as you learned to drive was a result of the increasingly stronger connections developing within your brain.
Imagine how your brain would respond if for your first driving lesson, your driving instructor drove you to the on ramp of a busy fast-moving 8 lane freeway and told you to take the drivers seat, get on the freeway, and immediately get into the fast lane.
Yet, sometimes in our zeal for self-improvement and personal development, we in effect try to jump right into the fast lane.
Set smaller goals that are specific and well defined so you know what action to take. You will also have more success with goals that are time-defined instead of vague references to the future: two months as opposed to sometime next year. They should be measureable so you can track your progress and challenging enough to provide a level of engagement but not so challenging as to produce stress and invoke error signals.
Breaking down large tasks into smaller portions also helps you to leverage Expectation and Repetition. By taking incremental steps, you can leverage the brains desire to automate tasks. As you build your expertise, your brain is developing the connections that allow the brain to perform functions related to your new skills in a less stressful, lower energy, more automated fashion.
The brain also uses past experiences to set expectations for future events. The brains experience of success through gradual steps helps set the expectation for more success which primes your perceptual system to look for confirmations of future success, not confirmations of past failure.