Ramadan is important to Muslims for multiple reasons.
First and for most is obedience to Allah (God) and getting closer to Him, then its beneficial effect on Muslim society as a whole and the increase of bonds, mercy and compassion between Muslims, and last but not least its self-disciplining effect on the person himself and how it helps him elevate himself.
In Ramadan, fasting starts from the first day until the last day. –No days off, no cheats, as God can’t be cheated! This is the part where it brings us closer to God.
The shared experience enhances the sense of unity in the community. Ramadan encourages to renew relations and end disputes.
And lastly, the Challenge itself, changing our habits and our experience with it cultivates motivation and self-discipline.