Motivation of the definition of compact operators for the non-linear case

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We know that we can study a compact operator between normed spaces $T: E \to F$ in two ways:

  • When $T$ is linear, it is only natural to ask that $\overline{T(A)}$ be compact in $F$ for all $A$ bounded in $E$;

  • When $T$ is nonlinear, it is natural to ask that $\overline{T(A)}$ be compact on $F$ for all $A$ bounded on $E$ and also that $T$ be a continuous map.

My question is: what is the motivation to ask for continuity for the non-linear case? guarantee the same classical characterizations for the linear case?