When you "milk" a business, you stop investing in it and just take the profits from it. You may even raise prices, which probably reduces sales volume, but may result in better short term profits. A company might milk an established brand that they see is losing its customer base.
Do liquidate is get out right now.
Milk is get out over time, taking cash out as you go.
Maintain is to keep up investment to keep business stable
Invested for growth is just that.
A company might sort its brands into these four groups