Is the latest forecast always the best?

In principle, that is how it should be. It happens, however, that the first few hours of the forecast take the "start-up" of some phenomena in the model, e.g. convection, so it is also worth looking at the results of the forecast calculated as the previous one. In addition, forecasts starting at different times may be based on larger or smaller initial data sets, which also sometimes influence the development of certain weather phenomena.