Testing a DCF valuation tool — where do these usually mislead investors?

I’ve been testing a DCF-based valuation tool recently, mostly to stress-test assumptions rather than rely on outputs. What’s becoming obvious is how sensitive intrinsic value is to relatively small changes in growth, terminal assumptions, and discount rates which makes me skeptical of sites that present a single fair value number without context. For those of you who actually use DCFs even loosely: • where do you think these tools most often go wrong? • data quality, normalization of FCF, capital structure assumptions, or something else? • do you ever trust automated outputs, or only use them as a starting point? Not trying to promote anything genuinely trying to understand what experienced value investors find misleading or dangerous in these models.