"It obviously is (a reality check)," he said. "I am extremely disappointed. We've had our moments and we did not take them. Having said that, South Africa were outstanding. Their bowling kept coming at us and one thing I know that was going to be tested was our young batting group. There are a lot of positives in that department.
"I think Babar Azam was amazing and he has taken his cricket to another level. Question marks have always been there surrounding Babar about his Test cricket. I think they will certainly disappear now. He will only go strength to strength from here now. I think Shan Masood played exceptionally well. Asad Shafiq played two innings and that was significant for us. Others chipped in from time to time. But we did not get enough runs."
The 50-year-old said there is no point blaming the coaching staff, but believes improvements need to be made in the batting department.
"Leave the coaches alone. The amount of work that Grant Flower puts in with these batsmen, it would be harsh (to blame him)," said Arthur.
"Certainly, the batsmen need to analyse their batting technique. There's a reason why no subcontinent team has never won in South Africa. Simply because the Asian guys here stay leg side of the ball which sees them get out to short-pitched balls. They need to be at the off side of the ball. We have got to develop a game-plan around those batting techniques. To a certain extent, we scored. But, there's a lot of work that has to be done."
Arthur, however, went easy on Azhar Ali who only managed 59 runs in the series at an average of 9.83.
"I reiterate Azhar Ali is a quality player. He will go through these form lapses, I guess," said Arthur.
"On a wicket that bounces, we need to do a little bit of technical work. There was a trend he got out four times in a similar manner and he admits it first up. He admitted yesterday that on Olivier's line coming back at him he should have kept his gloves down rather than keeping them up. As he goes away and plays for Somerset now, he will have some time off from us. And we will reassess when we come in September."
Pakistan's next Test assignment is in September against Sri Lanka, which will also mark the commencement of the Test Championship for them.
"We have got pretty high standards as a Pakistan cricket team. And we hate losing. 3-0 down doesn't sit well with me and I know it doesn't sit well down with the dressing room," said Arthur.
"I can never fault the attitude and work ethic that the squad has put in. They have worked hard on their skills. Our next Test series is in September which marks the beginning of Test Championship. We have a lot of time now to see and evaluate who fits in. The aim is to build a side that can win all around the world."
Meanwhile, South Africa head coach Ottis Gibson and stand-in skipper Dean Elgar praised the batting unit for putting up decent scores on the board.
"As bad as people have said the wickets have been, we got two quality hundreds and quite a few fifties," said Gibson.
"Temba Bavuma was outstanding in this series. He never got a hundred, but the job that he did. Hashim (Amla) in both innings in this match, and especially on the third day, we could easily have been bowled out but for the way Hashim played. And then Quinny (Quinton de Kock) scored a brilliant hundred as well.
"I keep saying to the batters 'when the wickets are like this, you don't need to score 500'. If we get 260 too in the first innings, with our four fast bowlers on a fast bouncy track that's a great score, because we know that we can knock a team over for under that, which we did. It's been tough for the batters.
"They might complain outside the dressing room, but inside the dressing room none of the batters are complaining about the pitches. We're just getting stuck in and trying to get as many runs as we can get to give our bowlers the chance to operate."
Elgar, who stood in as the captain for Faf du Plessis in the third Test, said: "Theunis (de Bruyn) is inexperienced at this level, and (Zubayr) Hamza came in on his Test debut, and that's always going to be tough. The pressure and intensity that you face at Test level is going to be higher than what you're used to at domestic level.
"You've got to have a few inexperienced guys around because they've got to take the game forward in a few years' time. So, it's important that we carry those guys around. They need to play, that's the only way you get experience. Unfortunately, you do have to go through a few failures in your career, but it's about how you bounce back from those failures going forward."
Gibson said the team will continue to play the brand of cricket they have been playing in recent years.
"We will certainly continue to play this brand of cricket, because it is successful, and ultimately that's what we want to be. We want to be successful, and if it's working for us then we'll continue this trend."
Dean ElgarMickey ArthurOttis GibsonpakistanSouth Africasouth africa vs pakistan 2018South Africa vs Pakistan 2018-19South Africa vs Pakistan 2019
First Published: January 14, 2019, 10:21 PM IST