Code decay is a reason that may cause involuntary end of
evolution. Although software is not material and is not subject to
wear and tear, its structure decays under the impact of software
changes [86, 87]. The symptoms of code decay are increased
difficulty of making software changes and decreased code quality,
particularly an increase in the presence of bugs introduced by the
changes. The situation may reach the point where further
evolution is beyond the capabilities of the programming team.