The upcoming (in 2.7.1) Ranked Missions only progress from wins. They are completed with 3 wins for the daily and 9 for the weekly. We will see how those amounts work in the wild and adjust accordingly.
Bioware, You've tried this before with only wins counting and it obviously wasn't working so you changed it so you could win or lose and still progress. You guys seem to do this stuff backwards.
Bioware finally added solo que to ranked but they eliminate 8 vs 8 ranked. Now they finally add a quest for ranked but make it so only wins count? LOL ...why act like it will be balanced and fun for those that lose over and over?