Why does a single radiator need regular bleeding?
When you do your daily bleed of this radiator if you don't actually get air coming out, just water. You don't have an air problem, you have a water flow problem.

If your system a diverter-tee system (a "one-pipe" system), check to make sure that the tees that feed this radiator are installed the same way as the tees that feed your working radiators. The diverter tee for this radiator should be on the return side, and the stripe (or other indicator of orientation) should be between the branches. An incorrectly installed tee could cause the exact problem you're describing.