So the arrow going this way is smaller than the arrow going in reverse. And what that basically means is the reactants A and B are thermodynamically more stable than the products C and D. And so if we plot this reaction on the following graph, the energy graph where the y axis is the energy state and the x axis is the reaction progress, this is what we're going to get. And notice that the energy values of these reactants is lower than the energy values of these products. And that's exactly what we mean by our reactants being thermodynamically more stable than our products. Now, what exactly does that actually mean about our reaction? Well, what it means is for this reaction to actually take place and for us to go from a lower energy level to a higher energy level.