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Context: Surveys in the visible and near-infrared spectral range haverevealed the presence of low-albedo asteroids in cometary like orbits (ACOs).In contrast to Jupiter family comets (JFCs), ACOs are inactive, but possesssimilar orbital parameters. Aims: In this work, we discuss why ACOs areinactive, whereas JFCs show gas-driven dust activity, although both belong tothe same class of primitive solar system bodies. Methods: We hypothesize thatACOs and JFCs have formed under the same physical conditions, namely by thegravitational collapse of ensembles of ice and dust aggregates. We use thememory effect of dust-aggregate layers under gravitational compression todiscuss under which conditions the gas-driven dust activity of these bodies ispossible. Results: Owing to their smaller sizes, JFCs can sustain gas-drivendust activity much longer than the bigger ACOs, whose sub-surface regionspossess an increased tensile strength, due to gravitational compression of thematerial. The increased tensile strength leads to the passivation against dustactivity after a relatively short time of activity. Conclusions: Thegravitational-collapse model of the formation of planetesimals, together withthe gravitational compression of the sub-surface material simultaneously,explains the inactivity of ACOs and the gas-driven dust activity of JFCs. Theirinitially larger sizes means that ACOs possess a higher tensile strength oftheir sub-surface material, which leads to a faster termination of gas-drivendust activity. Most objects with radii larger than $2 \, \mathrm{km}$ havealready lost their activity due to former gravitational compression of theircurrent surface material.

Why are Jupiter-family comets active and asteroids in cometary-like orbits inactive?