I am not a native english speaker so maybe I didnt express myself well


I believe that most of the people that are mining (like 70 to 90% of them) are people with average or mid grade salary (in real life jobs) and they have average to low grade hardware (most of them usb sticks,5 GH/s machines and some of them 500GH/s machines tops...)


So for those people if the difficulty exceeds lets say 6 or 8 billion they sure will quit since their hardware wouldnt even get them a thusandth fraction of a bitcoin per day in that difficulty so if and when they quit the difficulty should drop down (since 70% or 90% of the miners dont mine anymore having as a result the average time for a block to be found to increase noticably)


So at that time it should be a good idea do get into mining with a strong piece of hardware thats what I was talking about mine for a few weeks and then when people keep on coming back you just wait for the difficulty to raise up again.