Good evening Jayne,
I'm sure more experts will reply in more detail shortly. It sounds silly doesn't it! However if it's not to do with any debt problems in the past the lenders basically see you have no 'credit score' ie no way of measuring how you manage debt well such as regular payments -managable debt and in this current enviroment most think it's not a risk worth taking to lend.
However as they appear to see it , if you have some debt ie mortgage or credit card which you pay off regularly and correctly over time you build up a good credit history or 'score' hence their keeness to lend you money ie you are managing your debt well.
Still in this current enviroment lending criteria is getting stricter all around. One word of kindly advice do not consider firms that seem too willing to finance a loan or offer you that perfect deal be very wary.
Regards,
Paul