Visual cues that appear very clearly defined on one monitor can appear so differently on a different monitor that they no longer work well. For instance, borders that are clear, or distinctions in text color, or whether text in a highlighting color is comfortably readible.
When designing something visual, you want it to be clear to everyone, but you can't go out and buy every monitor.
What methods have been developed to avoid these troubles, given that you cannot test on more than a small sample of monitors and you can probably only develop and design the interface on at most two that you may not get to choose (the ones your company gives you)?
P.S. Feel free to answer outside the constraints of the question if it addresses the underlying problem in a budget way, e.g. maybe not the two monitors your company gave you per se, etc....