Washing machine twin inlet hose

[stratplus]

First time I've seen one of these. This was connected to the back of the same machine. Though machines were hot and cold feed or recently cold only. Why would you have a twin cold hose like this?

 

[stratplus]

Ok, so if you only have a cold supply and your machine requires both hot and cold then you need this "y" piece to connect between the machine and to the cold supply for the machine to work.
That I can understand, but if the machine is made to wash with a hot supply and you only connect a cold surely the machine won't wash as good with cold water only. Unless the machine has heating elements but then why would it need a hot supply?

 

[JCplumb]

They have heating elements even if they have a hot feed in.
It was deemed to be more efficient to heat the water in the machine rather than using the DHW so I'm guessing this hose was made so the manufacturer could still supply machines with hot and cold connections on the back.