What specific purpose plugin did you fall for marketed as do-it-all that didn't in fact do it all?

[billinder33]

That vocal thing from iZotope. Granted it was only sale for $15 (which should've been a red flag).

Edit: vocalsynth

I actually like this one as a 'sweetener' effect to lightly blend into a vocal. But I never expected it to be a do-it-all plugin.

[jules99]

Honestly, most analog-modeled EQ and compressor plugins. It's super rare that I test one and feel like it actually does improve the sound in a different way than a saturation plugin before a clean EQ/Comp does. Especially analog EQs. But that might be more matter of personal sonic taste than a generalization.

[martinjuenke]

This plugin was completely different from what I expected:
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