Retained earnings are important because if you invest in a company, you want to know they are earning money and are able to keep some for themselves. Looking at the balance sheet, of course you want to see some dividends because that means the company is doing well and internal people being incentivized, but you do not want all the money going out.
If you are looking at this number and it appears to be small compared to others in the industry, you may want to look at a few things. First, ensure the company has enough money to be paying dividends because if they are doing poorly and money is still going to shareholders, it may not be the best situation. Secondly, you want to take a look at the underlying health of the company and ensure sales and revenue is coming. If there is a critical error cause the low retained earnings, it may be an indication of what is to come. Lastly, this number may be low because they are reinvesting or paying larger dividends due to the success of the company. Be sure to fully understand the story to understand the rhyme and reason for the number.
Some companies pay constant dividends, some pay no dividends, and others pay dividend that are special, such as when the company is doing exceptionally well. The focus on dividends is important as it is a part of the equation and is one of the most controllable parts of the retained earnings.
This numbers is fantastic for fundamental research and should certainly be used in your research. In no way would it hurt looking at this number and it will only bring value. Be sure to look at other areas of the company and their financials because this may not tell the whole story. Retained earnings are important though because the company needs to keep some money for itself. If you get stuck, reach out to an investing community and bounce your ideas off of them. Should that not work, reach out to your investing professional and they can help to point you in the right direction. Retained earnings is a critical part in the balance sheet and needs to be monitored during and after you invest in a particular company.