What is a possible situation where someone may need to appeal a previous decision?

There are two situations where someone may need to appeal a previous decision:

If the decision was factually erroneous If the decision was legally erroneous

1) Appealing a decision based on factual errors are very rare. The court of appeal, in any case, will rarely accept any appeal based on factual errors. It is believed that the judge and the jury have done their job properly. Except of course if the error is so obvious it can't be ignored.

2) When there is improper, incomplete or incorrect admission or exclusion of evidence, it can lead to an appeal. Where any of the reasons exist, it has to be material enough to affect the outcome of the verdict for it to be appealed.

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