Joseph also said the lack of players who could turn a match was also affecting the side.
The team slumped to its third straight loss on Saturday night, going down 33-7 to the Waratahs in Sydney and, with the loss, any slim hopes of making the playoffs disappeared.
The Highlanders were always behind and failed to make any impact in the second half despite having plenty of ball.
"With about 60 minutes gone, the game was anyone's, though we were 19-7 down. But when you've got a player like Kurtley Beale, then he can do special things and he has been doing that to every team in the competition," Joseph said.
"Some teams have got a few of those players in their team. We have got one, Ben Smith, and we'd like to have a few more.
"I think the Highlanders have always been looking for those sort of players. But it is tough. We are in a competitive market and over the past few years not many of them have been keen to come down south. But hopefully this year we have shown that it is worth coming down here."
Joseph said he knew nothing about meeting All Black hooker Andrew Hore early this week to finalise a deal for next season.
The Waratahs were a quality side, and the Highlanders were always going to find it tough.
Joseph said the Waratahs had the advantage of having enough depth in their squad to target matches.
"We're not in a position like that where we can target certain games. What we needed to do this year is create momentum at the start of the season and I think we have done that ... if we have lost our first three games at the start and now ended up with eight wins then we would be rapt.
"But the way we are and the way we play this season was all about creating momentum at the start."
The Highlanders have one game left, against the Blues in Auckland on Friday night. A loss would leave the side with a 50% record.
The team has no major injury worries after Saturday night's game although it was found wanting at scrum time and halfback Aaron Smith was replaced at halftime after a forgettable first 40 minutes.
"It just showed that we perhaps haven't got as much depth as we thought we had and in some critical positions we have struggled this year. Pivot has been a bit of a problem all year."
The Blues will be desperate to win on Friday night to earn a home playoff game, but Joseph said his side was wanting to end the season in style.
"We want to finish well. It's been a long, long season and there has been a lot of injuries and we are now seeing the effects of that long, long season. The teams though that had nothing to play for in the past few weeks have been playing well, and that just shows how close the competition is."
