Buildup
If your detergent drawer is not cleaned regularly, it can contribute to leaks. Buildup results in water overflow in the drawer, which can leak out. For most washing machines, you can remove the dispenser tray from the drawer to clean it and the siphoning pieces. Warm water and a soft cloth or brush use regularly can prevent buildup from occurring.
Overfilled
If you add too much fabric softener to the dispenser, it will result in a leak. The dispenser tray has a max fill line marked on it. When you add the fabric softener, you should take care to not put in more than the max fill line. As long as you do that, you should be able to prevent leaks caused by overfilling.
Wrong Type of Fabric Softener
For some washing machines, using the wrong type of fabric softener or detergent can result in a leak from the dispenser drawer. If you have a high efficiency machine, which is designated by HE on the machine, you cannot use standard laundry products. Doing so will result in leaks. Instead, you must use laundry products with the HE listed on the packaging. Using the proper product can prevent this type of leak.
High Water Supply Pressure
While not common, a high water supply pressure can result in leaks from the dispenser drawer. This is because water overflows when released into the drawer, if the water supply pressure is high. You water pressure should be somewhere between 30 kPa and 1000 kPa. If you are not a plumber, you can call one to come out and check your water pressure if you suspect it to the be cause of your leak.