Most cardrooms use the significant action as 2 actions with chips and 3 without chips
i.e.
fold fold or check check is not significant
call call, call fold or call raise OR check check check for example are significant.
(If you are dwelling and can't see out the corner of your eye that chips are going into the pot and action is on you, take your bloody sun glasses off, and if you never heard a check or all-in, take your bloody headphones off
)
If you call time or it is noticed by the dealer before significant action. Then hand is still live.
There has been many times I have indicated to a player that the action is on them and players infront decide to pass/fold. If I call time and 5 people fold after I am not killing the players hand. And other players will get warning.