The diminishing returns on increasing amounts of capital in Cathay Biotech is a concern. The underlying trends in these areas are not favorable, suggesting it may be worth considering other investment options.

Low ROE and net income growth remains a concern for the company. Despite retaining profits, no earnings growth has followed, signaling other potential issues such as a business decline. Analyst forecasts suggest continued growth in earnings. The current share price may reflect this expected growth.

The diminishing returns on increasing amounts of capital for Cathay Biotech is described as a cause for concern. The stock's 27% fall over the last three years suggests that investors are cognizant of these changes and reacting accordingly.