It is an understanding of biological plant traits that will lead to successful rose cuttings. When you take a cutting, you have essentially removed the root area from that piece of plant material and it can no longer take up the water and nutrients that it needs. Plants, though, have a mechanism for regenerating lost portions of themselves. This is known as adventitious growth. Such an endeavor takes an enormous amount of energy and hormonal production.
Roses are no different.
However, we can aid in their endeavor by supplying a little extra boost. Most of you have heard of rooting powders, but you don't understand how they work or the proper method of application. This is probably the most misunderstood of all the processes listed above. In actuality, none of these procedures will give you the best results. Using powders is also not the preferred method.