Why do I not see a clear Red Dot
Does your dot look like the following
SMEAR - COMET WITH TAIL - COMMA
It is unlikely the optic is faulty but not impossible.
The common reason is that some degree of astigmatism is creating this situation which affects 1 in 3 of the worlds population and can vary with age.
The problem of astigmatism can not be solved by purchasing higher grade red dots as whether it is a £50 Red Dot or £1000 Red Dot this result would still be the same if you do have astigmatism.
To check optic is functioning correctly
1. With RDS held in your hand slowly rotate keeping head in same position if the distortion stay static and does not rotate this is most likely due to Astigmatism.
2. Use a camera or phone to take a picture of the Dot - It should appear perfectly round.
SOLUTIONS
1. Live with it as Red dot is designed for quick target acquisition and not ultimate precision.
2. Focus at distance not on the Dot in optic this can lessen the issue as dot is focused at infinity.
3. Brightness setting for light conditions is to high and can simulate astigmatism the higher the brightness the flaring will increase.
4. Use prescription glasses with astigmatism correct lens.
5. Polarised Glasses can help reduce problem.
6. Use aperture peep sight matched to height of RDS.
7. Use of Holographic sight (laser emitter rather than LED) could improve or worsen distortion depends on the person.
8. Or alternatively use Prism 1x sight with etched reticle with these there should be no astigmatism issues.