you don't have to be able to triple it, but something you could do on a bad day when feeling tired or sore. Also something you could do with a longer than normal pause.
The bar needs to be motionless on your chest, at the last comp I reffed at I got asked why I held a lifter for a while on the chest, but the bar was never stationary, if it stopped as soon as touched the chest he would have got the press call straight away
The easier your opener feels the more confidence you have for 2nd and 3rd attempts.