Complex sentence: When the hidden layers are larger than the input layer, an autoencoder can potentially learn the identity function and become useless; however, experimental results have shown that such autoencoders might still learn useful features in this case.
Split into simpler sentences: When the hidden layers are larger than the input layer, an autoencoder can potentially learn the identity function and become useless. However, experimental results have shown that such autoencoders might still learn useful features in this case.