The problem is not that a serious adjustment (sounds far better and actually more accurate than 'crash') will come but that it could come at any time this year or as you say early next year. If that adjustment is to a level 30% lower than we see today, not impossible, then how long do you keep an investment in the market gambling it won't happen until 'another day'?

At some point it could be wise to take money off the table and stick it away for the terrible 3% interest you'll get and just wait a month, six months or a year and take a 20% to 30% gain when you use it to buy back into market after the sell off.