My personal experience, to toss or take depends on you:
When I keep on writing, I find some mistake very easy to occur. But they really need to pay attention to avoid.

1. cliché. Don’t repeat others words. If really need, try to be creative and find a new way to express.
2. too many adjectives. Only use when you need.
3. Topic too big. Try to find small thing to reveal your point.
4. Too telling. Try not to persuade your reader believe you, but let them feel and follow.
5. the theme too sparse or too many to spread. It only confuse the reader. Poem should be more concentrated.
6. Lack of imagery or picture.