The FRW solutions are the basis of the current LCDM cosmological model. They include three possible spatial curvatures, positive, flat and negative. The last two possibilities imply infinite extension for any t>0, while positive curvature would give finite space for finite time by definition. Would these considerations lead to conclude that only the positive curvature case of the FRW cosmological model is used in the current inflationary LCDM cosmology? I mention it because it seems that only the topologically compact case with positive curvature is susceptible to be flattened by inflation, the flat case isn't for obvious reasons and the negative curvature because being infinite for any t>0 cannot be flattened any further by exponential inflation and in any case its original curvature should have been as small as the current measures error bars allow which is quite small.