The default creature designs (Frogger, Roo, Spider etc) are just body designs that have not been trained, so they obviously won‘t be good at their given task in the first generation.

As with your own designs as well, there is also no guarantee that they will learn to perform well with every simulation, given the random nature of evolutionary algorithms. Sometimes a complete restart of the simulation can significantly improve the effective learning rate because you might end up with a more diverse and promising set of randomly generated initial solutions.

That being said, there is also a pre-trained frogger simulation available in the list of saved simulations, in case you would like to witness a somewhat successful simulation of one of the default creatures.