The general idea is that someone who doesn't ponder these things will find it very difficult to reach perfection and vice versa. The sages are constantly engaged in this exercise and therefore find success in their endeavors. Those with limited capability should nevertheless set times to take to heart these matters, whether a maximum or minimum effort, and see success in their quest towards perfection.
After understanding the task of your requirement to introspect, I will now illuminate for you the items to ponder and research.