Cross-examination at trial gets all the glory. Maybe this is because television dramas focus on it. Maybe this is because of the hope that the lawyer will catch a hostile witness lying on the stand. Or maybe this is because trial lawyers' war stories seldom begin with "I was in the middle of this brutal direct examination when ... " Whatever the reason, direct examination is generally viewed as less interesting and therefore less worthy of lengthy preparation.
The fact of the matter is direct examinations can be more difficult to prepare and effectively execute. Trials are nearly always won based on what happens during the direct examination of witnesses. Seldom does the other side's case collapse because of cross-examination, no matter how skillful. A case is won when one side's presentation is more persuasive than the other side's presentation. Direct examination is the party's chance to tell its story, to explain its defense—in short, to win over the jury. The lawyers cannot tell the story as persuasively as the witnesses themselves, and even if the lawyer is a gifted speaker, nothing the lawyer says is evidence anyway. The jury will relate to the witnesses in spite of their faults and nervousness and imperfect memory.