In a market research, men identified three things 
as essential elements of achieving a satisfactory erection, including:
 Taken together these make up erection quality (EQ). Many men have been, or will be, concerned with the 
quality of their erection at some time in their life. It may be an occasional 
difficulty in getting or maintaining an erection; it could be an erection that 
is just not as hard as it once was; or it may be a consistent inability to 
achieve an erection.  It is estimated that over 30 million men in the US have 
experienced at least partial erectile dysfunction (ED). You are not alone if you 
experience a loss of erectile function. Fortunately, if you've noticed changes in your erection 
there is something you can do about it, talk to your 
doctor.