Why Is Quality Control Important?
The improvement of quality confers many benefits. Ensuring that work is being performed correctly reduces mistakes, thus reducing the need to redo tasks, reducing waste and thus keeping project costs under control. Higher productivity and increased worker morale resulting from such an atmosphere can help improve the competitive position of the company.
Consider two crews of the same size, skill level, and work activity. The first crew, but not the second, enjoys the benefit of having someone performing quality control duties. Any defective work can be corrected before work proceeds any further. On the other hand, any defect in the work made by the second crew will probably be discovered only after the work is completed. This defect in the work will be torn down and corrected or ignored and left in place. All this will cause problems as construction progresses, providing the owner with a degree of dissatisfaction. Customer dissatisfaction may even lead to the company being removed from consideration for future construction projects, or require costly corrective actions. Defects are not without their cost: the individual who made the mistake has accepted payment, while the person who fixes it will also be accepting payment, and expenditures for additional material and equipment will be required.
Consider the well-known case of the partial collapse of a parking garage in New York City. The absence of reinforcing steel in three out of six of the cast-in-place column haunches, which supported the main precast girders, caused this accident. The project plans and the rebar shop drawings showed that reinforcing steel was to be installed at these locations but was accidentally left out. As a result, extra work had to be performed at the contractor’s expense to correct the work and repair the damage post.
Another major quality blunder occurred when constructing a shopping mall in Qatar. After pouring the concrete for the columns and the slab, they found around 40% of the columns had a strength lower than the allowable strength. So due to the lack of concrete quality control on site and experience of the staff, this cost a lot of money to repair and also delayed the whole project.
Quality is often sacrificed to save time and cut costs. However, quality does indeed save time and money. Nothing saves time and money more than doing the work the right way from the first time, eliminating costly processes of correction from the outset.