Why media Pundits make such lousy tipsters

If you take the newspaper pundits and look at their average yearly performance you would find that you would be better off financially if you simply backed all favourites. Yes in any given year some will be profitable but this 'some' changes from one year to the next leaving you back with the average performance numbers. Why is it that they are so poor at making selections ?.  The answer I think lies in one of our inherent bias, familiarity breeds favouritism. Pundits first and foremost have to appear very knowledgeable about horses. It would not do for them to simply tip a horse because its number based on some mathematical formula was superior to the others. Pundits have to sound like they know what they are talking about and this in depth familiarity also comes with a cost. Getting to know horses makes it very difficult to decouple our thoughts from past favours done. A friend of mine gets to know a horse and if it does him a favour he cannot let it go and will invariably back it nearly every time it runs. As a result I got the expected email at the weekend when Cirrus des Anglais won. This familiarity for the majority of us is a hinderance. We think an in depth knowledge of a horse is a help but what extra insight gives us, in built bias takes away. I have very few 'personal' bets nowadays, my computer does all the betting, its much better than me at it.