Are games on Steam already up to date after the initial download?

I am busy downloading Witcher 3 now, and will probably be done in about a day and a half's time (slow connection here...).

I would just like to know: Will I still need to download the updates after I have downloaded the game, or does the initial download include the updates?

Steam shows the total download size is about 30.5 GB for me. Read on forums that download size was about 22.9 GB when the game came out. So that most probably means that patches, etc. are included in the current download. If anyone can confirm this, I would be grateful.

I'm asking because I had a bad experience with The Elder scrolls online, where the updates that I still needed to download were about half the size of the initial download (which was about 40 - 50 gigs IIRC).

UPDATE:

Finished downloading the game. It includes the latest patch, i.e. I did not have to download any additional patches to be able to play the game.

Most games do a complete download of all current patches on Steam.

However... MMOs tend to download the launcher and the launch version of the game. Then, the launcher will update the game on its own.

It's up to the game's publisher to keep the Steam copies of the game up to date and the MMO companies tend not to do that.

The largest offender I've seen of this is Planetside 2. You essentially ended up downloading the game again through the downloader. Basically, the game's internals were completely rewritten after launch, but the Steam version was never updated with this version.