Our genes are programmed for growth, growth gets out of control, leading to our death
The dynamic, wave-like model of aging aligns with the concept of quasi-programmed aging, which suggests that aging is not merely the result of accumulated damage, as proposed by the wear-and-tear model. Instead, aging reflects the unintended continuation of biological programs that were originally optimized for growth, development, and reproduction. These programs, including pathways such as mTOR, become dysregulated over time, driving aging and the onset of age-related diseases.
I may be reading this completely wrong but this makes me think of a possible mechanism of aging..
At the beginning of our lives there are processes that are turned on that signal for us to grow from babies to adults. Very abruptly these processes stop when we are able to reproduce or just after. But the stopping of these processes is never complete because tissues still need to be repaired, things physically still need to adapt. So now you have some subset of the original growth processes turned off (thus not causing adults to keep growing) but also have some subset that don't turn off. This combination of growth processes that are on and off causes "growth" without the macro growth of the adult but this causes aging.
Idk just a shower thought
You'd find this pre-print interesting: https://pubmed.ncbi.nlm.nih.gov/36973715/