Callbacks & Callback Hell

They execute too quickly
They use too much memory
They make code hard to read and maintain
Deeply nested callbacks create several significant problems: 1) Poor readability due to increased indentation and nesting, 2) Difficult error handling as errors need to be handled at each level, 3) Complex code flow that's hard to follow and debug, 4) Reduced maintainability as changes require understanding multiple nested levels, 5) Difficulty in implementing parallel operations, 6) Increased cognitive load when reasoning about the code's execution order.
They always cause infinite loops