It took me 4 months of daily study, combined with a full time job to be ready for the exams. Since it is my hobby and the books were fluently written, motivation was no factor.
I too know people who have tried the ATPL and they succeeded. Even after 18 months. That is a matter of personality and is true for whatever studies you take up.
TWR
Well done but your last statement about personality says it all. You have to be the type who will dedicate a block of time every day to the studies and we are not all like that. Working people with families also have priority commitments attached to their work or families which puts a ? over dedicating a block of time every day.
You could argue and his has been tried that all that study makes for better IR pilots. That has been proved to NOT be the case much to the dismay of EASA as in a major study the EASA and FAA pilots were compared with neither being safer than the other. The conclusion was that the training was different but the end result the same.
Pace