Why will most data given a large enough sample space resemble a bell curve or normal distribution?

Most data will resemble a bell curve or normal distribution due to the Central Limit Theorem, which states that the sum of a large number of independent and identically distributed random variables will tend toward a normal distribution, regardless of the original distribution. Additionally, many natural phenomena and human behaviors are influenced by a multitude of small, random factors that tend to average out, resulting in a concentration of values around the mean. This tendency for data to cluster around the mean and taper off symmetrically in both directions leads to the characteristic bell shape.