Statistics
If you like revelling in statistical nonsense OK.
I'm always appalled when I hear of an individual being told by an instructor "you will never make pilot", what arrogant nonsense.
One of the most enjoyable parts of being an instructor is to nurture an individual who is finding it hard to achieve their ambition. With patience and hard work it is always possible. The hours that they take will mean nothing when they succeed.
The RAF (CFS) are currently reviewing their whole approach to their initial training with just such a problem in mind. Sq. Ldr. Malcom Hunt outlined this problem a year or so back at the GAPAN Instructor Seminar held at CFS. They too had come to the conclusion that the chopping policy they had used to date had indeed lost them a significant number of very good pilots. Many that had excelled at the early stage had not always developed later and failed at much later stages of training. I've also seen this happen with PPL's over and over.
The overiding factor must be the quality of training. Currently we in the UK have no method in place to assess that. Training hours in most cases are relevant to the individual ability of the student. One problem that could occur if hours were to be published is that many some schools may start training only to pass the Skill Test and bypass the full syllabus where it is not actually examined.