Washing machines have always had soap dispensers to place the detergent in. For most people this is the best place for it. However, if you have problems with it not getting flushed down properly it might be better to try placing it inside the drum instead.
For a short while it seemed to become quite fashionable to use the drum instead. It’s less popular now because it doesn’t offer any functional advantages unless you have a problem when it’s placed in the soap dispenser drawer. You might prefer to put the detergent in the drum if your washing machine doesn’t flush it away properly, or maybe you just hate how the dispenser drawer gets clogged with detergent.
Placing it in the drum
If you do use the drum you need to use a proper container for the detergent. Do not just place the detergent on top of the clothes as this can mark or bleach the laundry. You can usually buy a specific detergent dosing ball, or most detergent manufacturers can supply one free if you contact them.
If using the drum it’s also even more important to make sure you don’t overload the washing machine. This is because detergent may get trapped inside laundry and be unable to disburse properly. That can not only prevent proper washing, but it also causes a potential safety issue (Detergent capsules danger to children).
One positive side effect of not using the soap dispenser is a cleaner soap dispenser drawer. But a side effect of placing detergent in a container on top of the washing is the noise of the container being tossed around the drum if it is made of plastic.
White marks or streaks on clothes can be caused by issues related to detergent being flushed from the soap dispenser drawer during rinsing under certain conditions. See this article for more details – white streaks on laundry.