It will be very interesting to see what changes for credit score calculations are made in the near future, with the idea in mind to make more people eligible for home ownership by enabling them to qualify for mortgages. Industry leaders are working with NAR toward making changes in how credit is scored.
Many people have a one-time tragic event that lowers their credit score, or in other cases are not recognized for consistent responsibility in making rent, utility and cell phone bills.
There just isn't a one-size-fits-all answer to credit score calculations, or agreement on what constitutes a reliable home owner likely to repay their mortgage.
Unfortunately even the most responsible home owner can have a tragic and unforseeable incident that prevents them from keeping up with their payments.