Expertise in the above 3 things get you a seat at the table. They constitute the core skill set that qualify you as a replacement level data scientist. If you have only 1 and 2, you can generate a lot of value as an analyst, but you’re blocked from scaling. If you have only 1 and 3, you’re basically a technician and your results won’t be trusted. If you only have 2 and 3 you’re basically a researcher, since data would need to be handed to you, and your iteration cycle will be too slow. So if you’re missing any of the above 3 things, work on those first.