Yo - great minds of the plumbing industry. Solve this for me, please.

Over the years I've repaired/replaced many a faucet - and have used several brands of silicone paste.

So? Well - I've noticed that the silicone that's on the various plumbing parts seems to last a LOT LONGER than the silicone paste I add - such as Danco, etc.

Am I doing something wrong? Are there silicones used by companies, and silicones used by mopes like me - that don't last very long?

I'd sure like to know - so I can go out and buy "the good stuff!"