Failure of fruit formation in rose may be due to several reasons. Some of the likely reasons are:
a. Rose plants may not produce viable pollen.
b. Rose plants may not have functional egg.
c. Rose plants may have abortive ovules.
d. Being hybrids, the meiotic process may be abnormal resulting in non-viable gametes.
e. There may be self-incompatibility.
f. There may be internal barriers for pollen tube growth and/or fertilisation.