From FindLaw: "Appeal in Error: Common Mistakes Made in Appeals," by Scott P. Stolley--
After a trial, the losing party often has too much at stake, emotionally or financially, to let the verdict stand unchallenged. Appeal is the next option, but many litigants do not fully understand how different an appeal is from a trial. They may also underestimate the differences between trial lawyers and appellate lawyers. These differences may be overlooked when inexperienced litigants launch an appeal.
The mistakes discussed in the article include selecting the wrong counsel, misanalyzing the appeal, and underestimating the costs.