Why does radioactive decay happen?

An element is said to be "radioactive" if the balance between the attractive forces holding the nucleus together and the repelling forces of the constituent particles is just stable enough to prevent an immediate breakdown of the element, but not stable enough to stop the gradual release of energy to reach a more stable final elemental state. This is because the second law of thermodynamics states that entropy (disorder) always increases (universally).

It is comparable to a herd of cows crammed into a yard with one broken fence section; while the cows remain "stable" within the enclosure, their pressure (order) is always trying to decrease (disorder); they are unable to simply fall through the broken section of the fence, nor can they pass through sequentially, as each must be positioned precisely in order for one of them to escape.

Thus, one cow leaves the herd on a statistically regular basis, thereby slightly altering its structure. Another cow leaves at a later date, and so on, until the herd reaches a size that is "stable" with the fence, at which point no more are forced to leave.

Radioactive decay occurs because unstable atomic nuclei seek a more balanced state. The process involves the emission of particles or energy from the nucleus, leading to a more stable configuration. This phenomenon is governed by the principle of achieving a lower energy state, balancing the forces within the atomic nucleus.