In the past, stains and their components were routinely made by the laboratory. Commercially available, premade reagents were uncommon and expensive. So, as an economical way to perform H&Es, techs learned to make the dyes as needed. The challenge was to make sure the quality of the stain was consistent. Different techs follow recipes using their own individual approach, so making dyes was typically left to one person. That said, there were also more techs in the laboratory, so the time needed to prepare the reagents did not take away from the overall workload of the team.
