If–ElseIf–Else works when you have outcomes coming in categories (weekdays being five days, weekends being two). When the outcomes are specific and/or too many in number, it could be a little tedious to use the If–ElseIf-Else construct. To understand this better, let's give ourselves a scenario.
The dress code at your workplace is decided by a child, who likes everyone wearing the colors of the rainbow. Since she does not like anyone working weekends, she's not a big fan of orange, and absolutely hates yellow. She has come up with the following scheme (she doesn't know of Monday Blues yet): red on Mondays, violet on Tuesdays, indigo on Wednesdays, blue on Thursdays, green on Fridays, and orange during the weekends.