Why sometimes it takes longer for new block to be made ?

[btctousd81]

ref: https://btc.com/

i am watching how often new blocks gets generated.,

imho i read somewhere , it stated new block gets generated every 8-10 minutes.

but sometimes it takes 30 minutes for new block to appear and sometimes more than 1 block gets generated in 5 minutes.,

why is that ?

who is controlling it ?

isnt there enough hash power already to generate blocks. ?

what am i missing here ?

[nullius]

imho i read somewhere , it stated new block gets generated every 8-10 minutes.

The target is 10 minutes.  However, that is only a probabilistic target.

but sometimes it takes 30 minutes for new block to appear and sometimes more than 1 block gets generated in 5 minutes.,

Or more—or less.

why is that ?

Two reasons:

0. The generation of a block is probabilistic; so how long it takes is dependent on luck.  Most of the time, generation time will be close to 10 minutes (a bit more, a bit less).  If one miner gets lucky, the time may be significantly shorter.  If all miners altogether get unlucky, then the time may be significantly longer.

1. Collective global hashpower (exahashes/second) is not constant.

who is controlling it ?

Lady Luck.  Who controls random results?  As aforesaid, it is a probabilistic process.  The time to generate a block is neither controlled by nor predictable to humans.

isnt there enough hash power already to generate blocks. ?

Yes.  The evidence is that blocks are being generated.  Time to do so is expected to fluctuate randomly, while usually being close to 10 minutes.

what am i missing here ?

The probabilistic nature of the process.

[btctousd81]

imho i read somewhere , it stated new block gets generated every 8-10 minutes.

The target is 10 minutes.  However, that is only a probabilistic target.

but sometimes it takes 30 minutes for new block to appear and sometimes more than 1 block gets generated in 5 minutes.,

Or more—or less.

why is that ?

Two reasons:

0. The generation of a block is probabilistic; so how long it takes is dependent on luck.  Most of the time, generation time will be close to 10 minutes (a bit more, a bit less).  If one miner gets lucky, the time may be significantly shorter.  If all miners altogether get unlucky, then the time may be significantly longer.

1. Collective global hashpower (exahashes/second) is not constant.

who is controlling it ?

Lady Luck.  Who controls random results?  As aforesaid, it is a probabilistic process.  The time to generate a block is neither controlled by nor predictable to humans.

isnt there enough hash power already to generate blocks. ?

Yes.  The evidence is that blocks are being generated.  Time to do so is expected to fluctuate randomly, while usually being close to 10 minutes.

what am i missing here ?

The probabilistic nature of the process.

so if all miners get lucky they can mine a block every minute ? theres nobody to tell them to slow down, becuase its just 1 minute since last block made.

Thank you.

[vv181]

If you'd like to understand comprehensively the subject, take a look at this reference
https://en.bitcoin.it/wiki/Confirmation
https://bitcoin.stackexchange.com/questions/3909/what-is-the-expected-time-until-the-next-block-is-found

[DannyHamilton]

so if all miners get lucky they can mine a block every minute ?

For as long as their luck holds out.

Eventually they run out of luck and it takes longer.

Imagine this...

I give you a standard perfectly balanced and fair six sided die.

You roll the die once every minute.

You "win" whenever you roll a six.

How often will you "win"?

Well, ON AVERAGE you will win once every 6 rolls.  The usual amount of time between wins will be close to 6 minutes.

Of course it is possible that multiple times in a row you could roll a 6.  As long as your luck holds out, you could keep rolling a 6 EVERY roll.  Eventually you will run out of luck and it will take longer.

It is also possible that you could get unlucky and it could take 20 or 30 rolls (20 or 30 minutes) until you roll a 6.

If you get lucky enough, is possible that you could roll a 6 on EVERY roll forever?  Sure. But, it isn't very likely at all, is it?