In Java, there is a practice of using keyword return at the end of a method. You can do the same in Scala, Example below shows it

 /* Scala code below resembles Java */
 def getErrorMessageWithReturnFirst(errorCode: Int): String = {

   /* A variable ('var') type which can change after declaration */
   var result: String = "Unknown Error"

   errorCode match {
     case 1 => result = "TCP Socket Failure"
     case 2 => result = "UDP Failure"
     case 3 => result = "Unknown Error"
   }

   /* Return the result */
   return result
 }

Scala code above can be improved with the help of expression-oriented syntax, Below given Scala code shows how match returns result

 /* Scala code below still resembles Java */
 def getErrorMessageWithExplicitReturnSecond(errorCode: Int): String = {

   /* A value ('val') type which can't change after declaration */
   val result = errorCode match {
     case 1 => "TCP Socket Failure"
     case 2 => "UDP Failure"
     case 3 => "Unknown Error"
   }

   /* Return the result */
   return result
 }

Scala code can be improved further, by removing val result declaration

 /* Scala code below somewhat resembles Java */
 def getErrorMessageWithExplicitReturnThird(errorCode: Int): String = {

   /* Control structure 'match' is returning a String */
   return errorCode match { case 1 => "TCP Socket Failure" case 2 => "UDP Failure" case 3 => "Unknown Error" }
 }

NO RETURN STATEMENT: An expression evaluates to a value, so there’s no need of return

/* Scala code below rarely resembles Java */
 def getErrorMessageWithoutReturn(errorCode: Int): String = {

   /* Control structure 'match' is the last statement in this method; automatically taken as return value */
   errorCode match { case 1 => "TCP Socket Failure" case 2 => "UDP Failure" case 3 => "Unknown Error" }
 }

Avoid return statement and prefer to have the last expression be the return value