Chelsea have struggled to make progress after a disappointing campaign last season, picking up five fewer points after 15 League matches than at the same point last year.
The latest defeat came away at Manchester United, the 2-1 scoreline flattering a Chelsea side who were well beaten and lost the midfield battle.
Asked why Fernandez and Caicedo have been unable to click as a midfield pairing yet, Pochettino said: “The relationship between them needs to improve, between them and individually.
“They are young. The expectation is massive when you arrive. It's not only the individual expectation but the collective expectation at a club like Chelsea. It is not easy, arriving not in the best place to perform quickly because they need to be part of the solution. They are not the cherry on the cake.
“When you arrive in a team in a building process and you’re young with not too much experience, even if you have good quality and people can see the club paid big money and only for that you need to perform.
“It’s because some people think in this way because they don’t know about football. It’s a process, it’s going to be a process. The moment is going to arrive that they are going to know better and to create this relationship that will help the team win games.”
James is another player who has received criticism, with his defensive issues highlighted after two bad defeats away at Newcastle and Manchester United.
Pochettino is still firmly behind his captain, who is yet to complete a full match this season. “I think the priority for Reece now is to build his confidence and fitness and work towards completing 90 minutes," the Chelsea boss said.
“Of course, we are competing and want to win, but what’s best for Reece is time and giving him game time. If not, it is difficult for him to be fit. If you ask me about both games [Newcastle and United] I think we cannot blame him and need to blame everyone. If you didn’t win, it is because something collective didn’t work.”
On James' start as captain, Pochettino added: “He is doing really well, I am pleased with him. But you need to remember for any captain, who is not playing because he is not fit or another problem, it is difficult to feel involved. But he is doing a fantastic job and I am so happy with him.”
Chelsea face a trip to Goodison Park on Sunday to face Everton. If the Blues drop more points, qualifying for next season’s Champions League will quickly look a remote prospect. “We feel really disappointed, sometimes frustrated, because we want to move so quick,” Pochettino added.
“But we need to stop and start again and start again and again. We need to understand that the process to build something is always...all that you have in your head to plan and to be strategic, but the reality, you know, it may be different and you need to stop and go slowly.
“At the moment, we need to go slowly because the results also have a big influence on the emotions in the way that you can adapt and assimilate the concept and everything.”