Maybe I'm naive, but I don't think any one denies the role luck plays in one's success or not. However, to completely discard effort and determination is selling everyone short. I'm running a successful company partially because of "luck", I happened to start it at the perfect time, but also because I pour every ounce of money and time I have into it. My nights and weekends don't exist. Some people aren't willing to put in the time to turn luck into success.
Telling people that success is just a matter of luck will only reinforce the thoughts of unsuccessful people to believe they're "unlucky". You are able to make your own luck to an extent.