You have asked your veterinary surgeon to examine the horse and advise you on its suitability for purchase. If they have put provisos on the certificate which they believe will not affect the horse’s ability to perform the tasks you require of it they are not saying that these provisos will never require veterinary treatment and you do then have the option not to proceed with the purchase. Choosing to accept these provisos is up to you but in some cases the underwriter would have decided on evidence based on the laws of probability that the risk is too great.
A perfect example of this is a horse which has been X-Rayed and shown to have a bone chip. Your vet who, will have the benefit of seeing the X-Rays and therefore assessing on an individual basis whether or not it is in a place likely to cause a problem, may advise you to proceed with the purchase. Underwriters however will look at their probability chart and see that bone chips often require removal at considerable cost and will therefore not offer cover on that particular aspect of the horse. Although it may seem unfair to you it is only by working within parameters such as these that it is possible to offer horse insurance at all. A similar situation is motor insurance, where Mr X who is 20 years old and has been driving for three years without problems is less likely to find cover for an expensive sports car than Mr Y who is 30 years old but only passed her test last week. This may seem unfair but the laws of averages show 30 year old drivers are less likely to have accidents than 20 year old ones.