It leaves much to be desired.

Meaning

It is unsatisfactory or disappointing.

Examples

• John: Have you seen the latest design proposal?
• Alice: Yes, and frankly, <b>it leaves much to be desired</b>. The color scheme is awful.
• John: I agree. The functionality also needs a lot of work.
• Alice: Exactly. The overall execution is subpar; <b>it leaves much to be desired</b>.