if 10 seconds is the rule, why is it no enforced during the game?
what does 15/ 10 mean?
It means that no matter how long you take over your moves, provided you don't run out completely you'll have 10 seconds for your next move.
Reduces time pressure blunders and the like.

If you take say 5 seconds to make a move, are the other 5 lost or is the 10 second bonus a permanent bonus?

if only 10 sec for next move, 'no matter how long you take over your moves' doesn't make sense... could it mean instead that if you make your move whiten 10 sec, those 10 sec are added to your total time..? thanks
I know it's a few months old now, and originally you responded to a 2 year old thread, but I'll explain it to you.
They are saying that you can take as long as you like, provided you don't run out of time on the clock, and when you end your turn it will add 10 seconds to your clock.
For example player A has 40 seconds on his clock and takes 38 seconds to make his move. He now has 2 seconds on his clock. But at the end of each turn 10 seconds is added to his clock, so he actually has 12 seconds. If his next move only takes 1 second he will go up to 21 seconds on his clock.
What is meant by take as long as you want, provided you don't run out of time means that if you run out of time before you end your turn you lose.

Maybe a simpler way to describe it is you start with 15 minutes on the clock and you get 10 seconds at the end of every turn.

Cumulative? Or no?
Wait, that's a stupid question. If you get the seconds, then you have the seconds on subsequent moves; therefore, cumulative it is.
KWW

That discussion makes no sense. There must be a plain, unambiguous statement of the rule. This is supposed to be a chess site, and no one has a statement of the rule? It's idiotic.

That discussion makes no sense. There must be a plain, unambiguous statement of the rule. This is supposed to be a chess site, and no one has a statement of the rule? It's idiotic.

Here's the official explanation from the help section:
How do the time controls work in the Live Chess?
Time Controls - Games on Live Chess are always timed. Conventionally, there are two numbers required to describe the time control:
- the first number is how many minutes you have to make all of your moves. 5|
- the second is how many bonus seconds you get for every move you make. |5
Another example:
18 | 10 represents an 18 minute game, with 10 seconds bonus time per move. So if you make six moves really quickly, those 10 seconds add up to an additional minute on your overall time.
If you like, you can have a game with no bonus time at all: 18 | 0 is an 18-minute game (no bonus).
Please click here for a description of how these time controls relate to Live ratings and the Seek graph.
what does 15 / 10 mean?