Buybacks may be more effective than dividends. If you consider your bought stocks as a source of income, then you get more control and better taxes with buy-back stocks.

With dividends you can't really rely on a future amount, i.e. you can receive more (or less) than you actually need. Also it can come at a different date that you want. Plus creates a tax event event when you maybe don't want to have it. And so on.

So it become more convinient to just have stock which you sell when you want and you sell exact amount as you need to. Also the tax rate on dividends is usually higher, especially if you hold the stock long enough.