For Neil Lennon these labours are somewhat hampered by light-fingered managers creeping on site and nicking his best players, and by the unavoidable truth that some recruits simply cannot be relied upon to form the foundations of his team.
The raw materials for Lennon and Celtic are untested, found in markets where there is no warranty or guarantee. Sometimes the recruits prove to be solid, even towering. Others are discovered to be frail, not able to support the weight of expectation or the exertion of pressure. It is a testimony to the robustness of the recruitment model at Celtic that so many of the new players fall into the former rather than latter category.
The consequence of that, however, is that Lennon, already promising a delivery of new building blocks in January, must accept that the best must leave the yard. Yet he pledges to build on. He can do no other.
The advance on the SPFL Premiership title continued on Saturday, buffeted both by the weather and a strong, uncompromising performance by a Hibernian team already stamped with the hallmark of Terry Butcher and Maurice Malpas.
Virgil van Dijk, the Dutch centre-back, admitted there was an opportunity for the team to go through the season unbeaten and attain the description of invincible in the league en route to a title that has surely been stripped of any intrigue as to its destination. "It is something that everyone dreams of," said the defender. "We have the quality to do it and have to stay focused. We are now 15 games unbeaten [in the SPFL], so we hope we can make this run last all season."
He also emphasised that he was determined to prove he could be part of Lennon's rebuilding at the club. "We are trying to prove ourselves to the manager," he said. "There were five new players in the summer and I was one of them. Everyone wants to be part of the team in the future, so the situation is clear for us."
The reality, of course, is that at 22 years old the £2.6m signing is already on borrowed time at the club. Lennon has identified him as the foundation of his defence but must know that the pilferers are waiting in the wings.
Van Dijk is better than Kelvin Wilson, the player he replaced. It would be ridiculous to expect this of every recruit but Celtic could be warmed on Saturday by indications that two other recent signings could make pleasing contributions. Teemu Pukki, the £2.4m signing from Schalke, has been assailed by criticism that this correspondent has found over-heated. The Finn may take time to adapt but he is an internationalist who has played in the Bundesliga and is far from the failure his detractors label him. His winning goal on Saturday will have bolstered the confidence of a shy character.
Nir Biton, at 22, another summer recruit, was neat and effective against Hibs. He is particularly adept at spotting the runs of full-backs and was always willing to receive the ball. There is the slight air of fragility about the youngster but he has the capacity to place himself at the centre of Lennon's plans.
A recruit of a different vintage is also slowly coming back to form. Emiulio Izaguirre, of the transfer class of 2010, has endured testing times but has retained his drive and threat in the final third although his attempt to impersonate Tom Daley was rightly punished.
However, in a week where the exit from the group stages of the Champions League could be viewed as inevitable - Celtic, after all, were seeded fourth and that is precisely where they finished - and domestic progress was unhindered, there is still a haze of uncertainty amid the rain of Celtic Park. The Georgios Samaras and Joe Ledley contract extension talks continue but both may leave. Mikael Lustig, the Swedish full-back, is an Barclays Premier League player-in-waiting and Fraser Forster an England goalkeeper who will be weighing up just which way to dive to make sure of the third-place slot in the squad for Brazil. Adam Matthews, the Welsh full-back, also has his admirers.
Lennon must prepare for the departure of at least some of this talent, perhaps a significant chunk. The indications are that he will try to bring in four players during the January transfer window.
The "work in progress" for Butcher shows signs of immediate improvement. Hibs were largely resilient and almost took their chance of leaving Celtic Park with a point. The most glaring impression - as if Butcher had begun his rebuilding with a splash of dayglo paint - was that Hibs were much better organised and that the management became more daring the longer Hibs stayed in contact with the champions. James Collins and Danny Handling at times formed a twin strike force and Liam Craig and Scott Robertson pushed forward on to Celtic's back four.
There was more than a hint of ambition about all this and that trait has to survive at both Celtic and Hibs. There are different expectations at both clubs and the works in progress must be built in the most challenging of economic terrain. Butcher and Lennon, however, are not the sort of gaffers to shrink from such a shift.