You can have decent algorithm skills and not be able to demonstrate that in an interview environment. You get more than 20 minutes in the real world and you're

You can have decent algorithm skills and not be able to demonstrate that in an interview environment. You get more than 20 minutes in the real world and you're allowed to do research. Most algorithms that developers will commonly need to use already exist and the skill is not developing algorithms but recognizing which to use and when. Understanding it enough to adapt it to specific needs. That's not the skills interviews test for.