Have you been thrilled to find that there is publicly available data for a project similar to the one you're about to start and had your hopes dashed against sharp rocks because the files uploaded make little sense?
Have you thought about testing your new data processing pipeline for someone's old data and read 300 pages of supplemental information to discover they never tell you what file is what?
The thing that is missing from that experiment is MetaData. (Pronounced like "Mee Ta Da Tay; imagine that 90s star wars character with the big ears saying it. It's like that.)
And a bunch of busy bodies are trying to fix this problem by annotating data previously deposited and by giving us some templates for how we can annotate the things we upload. Strongly recommend you check this out. It'll be great for all of us!