J.C. Penney (JCPN.Q) shares finished up 8% today after the struggling retailer reported its latest earnings and investors responded to positive momentum. Though comparable sales were down 4.8% in the quarter, October comps saw a 0.9% rise, and CEO Myron Ullman promised continued sales improvements in the fourth quarter.

Still, J.C. Penney dug such a hole for itself under former CEO Ron Johnson that a true comeback -- getting to positive earnings -- is going to take years, if the company can even get there. Fool contributor Jeremy Bowman explains below.