Evolution leads to a set of separated simple stable or periodic structures. Evolution leads to a chaotic pattern.
Evolution leads to complex localized structures, sometimes long-lived.
Intuitively, according to this classification, one should only expect gliders, Turing-universality, and similar complex behavior in class 4 automata. This result throws the usefulness of this classification system into question. If a rule includes B0 or B1, any pattern expands to infinity in all directions, no gliders can exist, and the question of whether a pattern lives or dies can not be universal. No pattern expands. No pattern contracts.