Make Equal

You are given an array $A$ of length $N$. You can perform the following operation on it: - Choose any index $i$ such that $1 \lt i \lt N$ and $A_i$ is not smaller than either of its neighbors, i.e, both $A_i \geq A_{i-1}$ and $A_i \geq A_{i+1}$ are true. Then, decrease $A_i$ by $1$. Is it possible to make all the elements of $A$ equal by performing this operation several (possibly, zero) times?