“Shooting down ideas” gets a bad rap.
There’s an idea out there that all ideas should get their time in the sun. So naturally too-early critique (or any critique at all) can sometimes get tagged as anti-creative or even a bit selfish and anti-social.
While I understand the point*, it also doesn’t quite take into account the scarcity of time.
Let’s say you’re trying to build an airplane. For every idea acted upon (or even considered), there’s another idea that doesn’t get the time of day. There’s an “opportunity cost” because there’s an opportunity lost every time you dwell seriously on one way of building a plane as opposed to the several dozen other possible ways.
If you have already tried and failed to build a working plane with goose feathers and plywood strips, there’s no shame in “shooting down” a similar or repetitive idea. If, in the spirit of niceness and “giving every idea a shot,” you let yourself and others work on a goose/plywood plane, you’re not just likely to fail. You’re also likely to miss the plane construction schema that would have worked.
There’s no value in artificially creating space for bad ideas. And don’t be afraid to call ideas for what they are (assuming you have a good case). It may be a negative thing to have to “shoot down” an idea somewhat else has brought to the table. But the effect is positive: it creates the open air space for someone else’s better idea to get off the ground.
* Most ideas need a bit of time to get off the ground, conceptually-speaking. And often we need time to wrap our own heads around what might be novel and useful in someone else’s idea.