Soaps, especially daytime soaps have to do a lot more recasts than most other shows--likely due to the daily format. The grueling schedule makes it harder for some actors to turn out their best work, and even if they do okay, they may burn out a lot quicker and leave rather than continue to work 60-hour weeks. This means very few long-running soap characters are still being played by their original portrayer. Legacy characters (characters who are "born" on the show and grow up before our eyes) are usually the ones recast the most, since they get aged quickly and often have to be written out and brought back for various reasons. Kevin Buchanan of One Life to Live had twelve actors play him from childhood (born 1976) to the show ending in 2012. Chris Hughes of As The World Turns had nine actors (1986-2010) and Jamie Frame of Another World, ten actors from 1970-1993. One of the problems inherent in such recasts, however, is that the character would be aged several years with each recast, while the actors playing the parent(s) often stayed the same and aged at the normal rate. This is why Jamie's mother Rachel gave birth to twins despite Jamie having made her a grandmother eight years prior.
All aspects of daytime are done in a hurry, and occasionally it is reflected in the casting process. In other words, they sometimes hire an actor in haste and they turn out to be a bad match for the role. One actress, a newcomer named Charity Rahmer, was infamously hired for a role on Days Of Our Lives and turned out to be so bad at the part that she had to be replaced before her taped episodes even aired. They had done the same audition process they always do, and she had appeared to be the best person for the part...but apparently not!
Sometimes recasts are done to "take a character in another direction," which can be translated as "we didn't like how X was doing our material," or perhaps "We want to start over with this character since X screwed up so badly". The popular character of Nicole Drake on The Edge of Night "died" in a boat explosion. When they decided to bring her back, they recast with an actress fifteen years younger and made what was a matriarchal character into a "ingenue in jeopardy," a major movement in another direction.
Other times, the show wants the recast to be as un-noticeable (and as uncontroversial) as possible, so they go out of their way to recast with someone similar in looks and mannerisms. When Amy Carlson left her role of Josie Sinclair on Another World, they recast Josie with Nadine Stenovitch, and actress who looked so similar to Carlson that many people thought she WAS Carlson. Stenovich even wore recognizable pieces of Carlson's wardrobe when she played the character to ease the transition.
