It isn't necessarily a move on the attorney's part to continue the trial to a later date. Conflicting schedules of the defense, prosecution and other trials come into play. For instance, a court may schedule 6 trials on one day knowing that most of them will settle (civil) and some will ask for continuances. The court is trying to make sure that days aren't wasted without trials taking place. If a trial that was scheduled before yours actually goes to trial, the court must continue yours. Hope I am being clear.
It's a PITA if it is done at the last minute because you have alreaedy served subpoenas on witnesses, scheduled experts, readied the staff, continued other cases or depositions and spent all your time preparing for trial. Then you walk into the court room with all your evidence and briefcases and learn that you've been continued. Then it's a matter of having everyone in the office contact all the people who were coming to the trial to tell them and you have a very mad and confused client, dressed for court, tired from a sleepless night and the hours of prep.
And a few months later, you get to do it all over again.
And, when the court requests the continuance or it is due to court conflict, one of the attorneys is asked to prepare the paperwork for filing and signature by the Judge.