Not downloading the best quality format served as a single file

[numlockkey]

Checklist

• I'm reporting a broken site support issue
• I've verified that I'm running youtube-dl version 2019.11.28
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar bug reports including closed ones
• I've read bugs section in FAQ

Verbose log

C:\Users\T5400-3>youtube-dl -v -f best "https://www.youtube.com/watch?v=qBYbqh4QgNU"
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['-v', '-f', 'best', 'https://www.youtube.com/watch?v=qBYbqh4QgNU']
[debug] Encodings: locale cp1252, fs mbcs, out cp437, pref cp1252
[debug] youtube-dl version 2019.11.28
[debug] Python version 3.4.4 (CPython) - Windows-10-10.0.18362
[debug] exe versions: ffmpeg 4.2.1, ffprobe 4.2.1
[debug] Proxy map: {}
[youtube] qBYbqh4QgNU: Downloading webpage
[youtube] qBYbqh4QgNU: Downloading video info webpage
[debug] Invoking downloader on 'https://r4---sn-p5qlsnd6.googlevideo.com/videoplayback?expire=1576192169&ei=SXTyXZTdArmwhwb2z7GQBA&ip=216.55.242.167&id=o-ACDYYCcuJkeLXB_oFY2RpTl15pZ9Dl2wmks9GAx0FLfU&itag=18&source=youtube&requiressl=yes&mm=31%2C26&mn=sn-p5qlsnd6%2Csn-ab5szne7&ms=au%2Conr&mv=m&mvi=3&pl=20&initcwndbps=4408750&mime=video%2Fmp4&gir=yes&clen=35399787&ratebypass=yes&dur=1194.202&lmt=1404864718190430&mt=1576170421&fvip=4&fexp=23842630&beids=9466588&c=WEB&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cmime%2Cgir%2Cclen%2Cratebypass%2Cdur%2Clmt&sig=ALgxI2wwRQIhAKSZ8HWaql8JiLi3STsUyEYfZZ34_SdX3Gkjf-2pjJsBAiAjFi1Eu967hrgc5EW_JmRt8NszLKxMhEgK2BZ5zsEsQw%3D%3D&lsparams=mm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AHylml4wRQIhAMPp9McyAu0omOOhXy2WV7f67eCMEIBqNbyxScC_7hevAiBo2XRmiFWZGu2UaSMUHO-zJFnLWJiXVjl7XVmBPhSaeQ%3D%3D'
[download] Destination: Encoders, Decoders, Code Converters, and Parity-qBYbqh4QgNU.mp4
[download] 100% of 33.76MiB in 00:04

Description

I want to download the best quality format served as a single file from this URL: https://www.youtube.com/watch?v=qBYbqh4QgNU

The file that gets downloaded is only 640x360 resolution even though 720p version is available.

[dstftw]

Read FAQ on format selection.

[numlockkey]

I've read it, and it's not doing what is supposed to do, or am I missing something?