This example demonstrates benefits of using fold/cata instead of map and getOrElse on Option[T]. There are, of course, occasions when pattern matching is preferable as well.

OptionMap.scala

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scala> val opt: Option[Int] = Some(10)
opt: Option[Int] = Some(10)

scala> val typeCheckFail = opt map (_ + "2") getOrElse (3)
typeCheckFail: Any = 102

scala> val typeCheckWin = opt.fold(3)(_ + "2")
<console>:8: error: type mismatch;
 found   : String
 required: Int
       val typeCheckWin = opt.fold(3)(_ + "2")

scala> val typeCheckFailAgain = opt match {
     |   case Some(x) => x + "2"
     |   case None => 3
     | }
typeCheckFailAgain: Any = 102

scala> val patternMatchOops = opt match {
     |   case Some(x) => x + "2" //At least I get a warning here
     | }
<console>:8: warning: match may not be exhaustive.
It would fail on the following input: None
       val patternMatchOops = opt match {
                              ^
patternMatchOops: String = 102