Difficult cuttings CAN be rooted. Root cuttings by Quick Dip. Use fertilizers and fungicides with care. Two easy ways to produce symmetric roots. Transplants have improved success.
Roses have higher flower yield.
Since Medieval times plant growers have known that many plants can be propagated from cuttings. The new plants have the same characteristics as the parent plant. Some cuttings root easily, some with difficulty and some never on their own. In the 1930's horticultural researchers isolated the plant growth regulators which promote rooting of cuttings and improve the root mass of rooted plants. These regulators even produce rooting of some cuttings which do not self root.