The 20-year-old had been on the Anfield books for four years but opted to throw his lot in with the Hornets last summer after leaving Merseyside on a free transfer.
The hope was that the Birmingham-born hit-man would see more game-time but that has not happened, with just six appearances in all competitions.
The youngster has scored only one goal and has yet to find the net in the Premier League amid rumours Watford head coach Walter Mazzarri is considering sending him out on loan in January.
Whether or not that happens only time will tell but Sinclair has backed his summer choice and feels he is at a progressive club.
"To me, it was an exciting opportunity to further my career at a club that’s growing," he said.
"I played here in an FA Youth Cup tie three years ago, and one side of the ground was missing - so you can see how much the club has progressed.
"We’re trying to cement our place in the Premier League and kick on towards those European places. It is very important for the young players here to see there is a pathway to the first team."