I'm in a writerly-giving-advice mood. The little editor inside my head has been working overtime, poor bastard.
Notice how the simile in the title, besides being completely odd, doesn't tell you what the subject (she) *is*. She's like a pile of turds on a summer's day, but what *is* she, per se? This has been an issue I've noticed ever since the great writing guru known as Rez pointed it out. Most similes don't actually tell you anything. It's all beating around the bush.
To put it into perspective (with my brilliant analogy):
Say I hand you a cup filled with hot brown liquid. You ask if it's coffee, and I reply, "It's like coffee."
I think we can agree that that response doesn't tell you what you're actually drinking -- in which case, I wouldn't drink it if I were you.
That doesn't mean similes are bad, though, I like to use them sparingly -- but that's just me. There is an easy fix for this, and that's adding in what exactly the simile is referencing, because you can't compare two things if you don't mention one of them.
So we would say: She's disgusting like a pile of turds on a summer's day. Now we know what she *is* (disgusting), and thus the simile helps to build on that knowledge, which is, disgusting in what way.
Next time: Cliches!