Not programming outside of work is an indicator rather than a cause of 'bad programmer'.
Programming outside of work indicates that you like programming. If you are bad at programming you will not like programming, as it will be frustrating.
It also indicates that you are reasonably smart, probably get bored watching television, and are at least a little intellectually curious. If you are specifically programming something 'fun' to unwind after a long day of work, you are clearly comfortable programming, and you have interesting (enough) ideas about what to program.(It also indicates that there are no decent pubs within walking distance).
If you are programming in your free hours because some guy on stack overflow said 'this is what you must do to be the greatest programmer,' you are probably an idiot. No amount of outside work programming will help you.
Programming outside of work indicates that you like programming. If you are bad at programming you will not like programming, as it will be frustrating.
It also indicates that you are reasonably smart, probably get bored watching television, and are at least a little intellectually curious. If you are specifically programming something 'fun' to unwind after a long day of work, you are clearly comfortable programming, and you have interesting (enough) ideas about what to program.(It also indicates that there are no decent pubs within walking distance).
If you are programming in your free hours because some guy on stack overflow said 'this is what you must do to be the greatest programmer,' you are probably an idiot. No amount of outside work programming will help you.