Fizzle (verb)

1. To make a sizzling or hissing sound and cease to burn brightly.
2. To die down or come to an end gradually, especially in an unimpressive or disappointing way.
3. To fail to live up to expectations.

Origin:

Of imitative origin.

Examples:

1. The firework fizzled out and didn't explode.
2. The party fizzled out by midnight.
3. The company's new product launch fizzled and failed to generate any significant sales.
4. The plan fizzled out due to lack of support.
5. The relationship fizzled out after a few months.