Having a solid plan for sideboarding is important for three reasons: You identify which cards you will be taking out and putting into your deck , as swapping out the wrong cards could greatly hinder your deck's ability to function
What players need to know about Dimir is that they have some expensive casting cost cards due to the cipher mechanic and because many of the staple tools have mill or library destruction baked in
Investing in collectibles like metal Pokmon cards, a set that included certain year information, has some risks due to manufacturing and damage counters, including weakness, resistance, and packaging issues
And frankly, I'll take losing to Kaalia to most of the other Commander powerhouses because at least she feels fair
Unknown Shores
A nice simple one is just that the option of doing nothing, or at least casting nothing, is a bad option when you are behind or even yet can often be the best option when you are ahead