RNNs are not perfect, there are two main issues namely exploding gradients and vanishing gradients that they suffer from. To understand the issues, let's first understand what a gradient means. A gradient is a partial derivative with respect to its inputs. In simple layman's terms, a gradient measures how much the output of a function changes, if one were to change the inputs a little bit.
Problems and solutions to gradients in RNN
Exploding gradients
Exploding gradients relate to a situation where the BPTT algorithm assigns an insanely high importance to the weights, without a rationale. The problem results in an unstable network. In extreme situations, the values of weights can become so large that the values overflow...