The Belgium international defender is enjoying a good start to the season and has now started back-to-back Premier League matches for the Hornets, helping keep a clean sheet in both.
But he admits he can't be sure he will keep his place for the visit of Manchester City next Saturday because head coach Silva could change his mind at the last moment.
He told Belgian radio: "No, I do not even know if I'm going to play next week, but I'm going back to training on Tuesday.
"[We find out the team] Two hours before the match. It is never assured that you will be on the pitch even if during the week in training we see more or less the idea of the coach.
"For example last weekend there was a team set up and finally he changed a player between Friday's training and Saturday's game. We are never 100 per cent sure."
Kabasele reflected on the start Watford have made this season, which sees them sitting fourth in the Premier League table.
He said: "Manchester United, Manchester City, Chelsea and then Watford, who are among the top teams, we're taking advantage of it!
"We take on [Manchester City] with a lot of fun, confidence and we are in the best position to attack this match."
And the ex-Genk centre-back revealed that he was never close to leaving Vicarage Road over the summer.
"It was never a question for me to leave Watford during the transfer window," he added.
"The leaders were satisfied with the matches I played in last year, there was no door open for my departure. I played in all the pre-season matches which also reinforced the idea that a departure was not going to happen."