The morphological metastability of spontaneous crystallization from the melt of short-chain semiflexible homopolymers was studied through dynamic Monte Carlo simulations of a lattice multiple-chain system. Frictional hindrance for the sliding diffusion of the chains in the crystallites was employed to enhance the metastability of folded-chain crystallites, and distinguish the polymer crystallite from its mesophase, though their phase transitions have the similar driving forces. The integral folding of short chains in the crystallites and the constant linear crystal growth rate were identified with the actual polymers. In addition, the roughness of the local growth front accompanied with the occasional reversals and jumplike advancing was observed, which cannot be explained by current models, The crowding of the dangling ends on the fold surface seems to be the main reason for suppressing the lateral growth front, and the mechanism of chain folding was proposed. Its implications to the special behaviors of polymer melt crystallization, such as the semicrystalline state, the effect of the chain rigidity and molecular weight to crystal growth, the reversible premelting, and molecular segregation are briefly discussed.