What can cause a low milk supply

Breastfeeding is very rewarding but it can be VERY hard work.
One of the things that can be tricky for some moms is low milk supply.
There are loads of factors that can cause milk supply to decrease but the most common one is lessening the amount of time your baby feeds. Your milk supply will automatically start to lessen when you decrease feeds and sometimes this is done to soon.
Here is a list of some of the causes.
Supplementing with formula will naturally decrease your milk supply
Nipple confusion which can happen when introducting bottles, dummies and nipple shields.
Scheduled feeding.
A sleepy baby and encouraging your baby to sleep through the night too soon.
Cutting nursing sessions short
Skipping breastfeeding sessions
Health or anatomical problems with your baby
Health problems with you such as anemia, retained placenta, postpartum hemorrhage, hormonal disorders, thyroid problems etc.
Certain medications can effect your milk supply
Smoking or alcohol consumption
Early introduction to solids
If YOU have rapid weight loss
A previous breast reduction
Anything else you'd like to add to the list?