- Based on the experience gained since the beginning of the plant variety rights system in 1961, it became obvious that, at least for some species, the minimum distance between varieties was decreasing and so, although the varieties were declared distinct, the quality of the protection was decreasing. The introduction of statistical tests to establish distinctness, in particular for species with relative uniformity, was also questioned because the differences were not necessarily visible.
- In addition, the fact that characteristics used to establish the description and decide on distinctness were, in general, not linked with the value of the variety was increasing the concern of the breeders when very similar varieties were protected independently from the initial variety.