A bullet is rapid.
A leopard is rapid + agile.
AGILE × RAPID × LEAN
Agile development is different from rushing to an end goal. It is the ability to maneuver quickly in response to change. If a bullet misses its target, unable to maneuver midstream against a moving target, the entire process must start over from the beginning.
In a previous job, we abused Scrum by neglecting its Agile core. We took a Waterfall approach to the Scrum framework. While this can get a group of developers to a goal, there is a high-stakes cost when things go wrong, when Waterfall overshoots the goal because it was not checked properly by Agile concepts.
Increments in Agile are smaller, tighter, and taken to the end user faster for early feedback to guide the goal. This lends the development team a significant advantage over the clunky full development of an entire module before going to the client.
In our case, the Sr. Engineer dreaded his end-of-sprint talks with the client because of all the change requests and complaints being made. His presentation had to be longer, and client response was a particular headache.
This is precisely what Agile was developed to resolve.