Unfortunately for Coventry, they have such a weak squad that their rugby isnt't good enough to pull in the fans - Don't get me wrong, they play with plenty of heart, but their players simply aren't of a high enough calibre.
Another problem for them is the abundance of other established clubs locally who will prize fans away. Leicester and Northampton are the obvious pair, but Bedford are also one of the most famous teams in the world while Nottingham have a good chance of becoming a Premiership side after next season.
It's a sad tale for what was the most dominant side in the country once upon a time, but that's the sad downfall of the dod-eat-dog world of pro era. The same thing happened to Orrell (although Wigan RL also had a lot to do with stripping their assets). I fear this won't be the last time an established and historical club suffers - A pitty they're not in London or the west country. The RFU would bail them out if that were the case.