One of evolution’s truths is that it always goes forward. However, a trait than causes it to degrade and bring evolution to a standstill is also generally understood as evolution. It is not predestined, as some might suppose.
In other words, evolution has no clear focus.
In an articled in Science Daily, the evolutionist David Fisher shows that traits can also degrease: “The research appears in the Journal of Evolutionary Biology, where lead author David Fisher shows that the increased evolution of selfless traits -- such as sharing food and keeping watch for one another -- is mathematically equivalent to the decreased evolution of individually beneficial traits.”
He then goes on to explain.
“For example, a fast-growing tree may take all the sunlight, water and nutrients out of the environment, causing its neighbours to grow slowly. In the next generation, more trees are fast-growing but are also nasty neighbours. As a result, negative social effects are much more prevalent, and so everyone's growth is reduced.”