The Finn says he understands why there is speculation about his own future with the Scottish Premiership club.
But he said: "It is only natural when we are where we are.
"When you look at the signings we've made, we wanted to add strength and experience into the side and we did that."
Paatelainen, who replaced the sacked Jackie McNamara in October, has been unable to lift United off the bottom of the Scottish Premiership.
He bolstered his defensive options by signing Japan goalkeeper Eiji Kawashima, previously of Standard Liege, former Ivory Coast defender Guy Demel, who left West Ham United last summer, right-back Kyle Knoyle arrived on loan from the Hammers, while Gavin Gunning returned to Tannadice from Oldham Athletic.
Up front, Paatelainen added former Liverpool striker Florent Sinama Pongolle, who had been released by Lausanne-Sport, and Finland forward Riku Riski on loan from Rosenborg.
The United manager stressed there was "always an element of risk" when bringing players in who are without a club or available during the January transfer window but thought he had added quality.
"We've been here a few months and I think we have improved," said Paatelainen. "But this is by no means our team.
"But, all credit to the players, the way we have improved is a definite plus, but the same mistakes, the same softness keeps resurfacing and that's really disappointing."
Paatelainen says he has not spoken with United chairman Stephen Thomson since shortly after Saturday's home defeat by Hamilton Academical, which left United eight points adrift at the bottom of the table.
However, while recognising there is always the possibility he will lose his job, the manager continues to plan for next season, whether or not they are relegated.
"I am determined to build this squad and make sure we bounce back stronger," added Paatelainen.
"We need to make loads of changes, player-wise, personnel-wise and I am determined to do that.
"We know what needs to be done and we have clear plans. We have targeted players already.
"The budget will be cut severely anyway, regardless of where we are. There will be much less money next season.
"It will be a smaller squad but will be a much more effective squad with more steel to it."
Dundee United manager Mixu Paatelainen has defended his signings since taking charge in October despite his side being on the brink of relegation.