The Brief Overview of Traditional Publishing:
The road to publication is fraught with double standards, slow moving processes, scams, inspiration, and grit. Exciting, right? Getting to publication is kind of like an adventure/mystery novel.
When I started poking around, I got a lot of congratulations for completing my manuscript. "That's the hardest part, and so many people don't get to this point." And, yes, the completion of a manuscript is no small thing, but I can't say I agree that it's the hardest part. While many manuscripts never get completed, of the ones that do, many disappear into a void during the journey to publication.
I knew I wanted to publish, but I didn't have a strong inclination toward traditional (trad) publishing or independent (indie) publishing, so I started digging into both paths. A lot of people have strong opinions one way or the other about what is the best path, but at the end of the day, it seems to me that every author is taking a big risk regardless of the path they choose.
In trad publishing, you generally need to first convince an agent to sign with you and to do that you need a query letter, a one-page summary, and a one or two sentence pitch to start. The query letter is akin to a movie teaser. In approximately 350 words you want to make your manuscript eye-catching but not reveal spoilers, include why you are querying this specific agent and, if appropriate, include some of your own qualifying background. This means you must spend some time looking into the agents, but not too much time, because agents periodically close themselves off to queries! And as you look into agents you will find that they can take several weeks to reject or accept your submission. Sometimes a rejection is simply no response. Sometimes agents can ask to see more of the manuscript, ask for changes to be made, and still wind up rejecting it.
Depending on the genre and style of writing (how on-trend or nuanced the work is), authors can easily spend a year or a few years in the so called 'query trenches' sometimes completing other manuscripts before the first one is agented. Once other manuscripts are in the works, authors tend to 'shelve' the older work and while some reappear later, others never see the light of day. Once an agent is secure, there's still the matter of getting the publisher on board, which will largely be determined by who the agent knows. Once the publisher is locked in and you as the author have relinquished control of your work, it'll still be several months of editing, cover design, and more editing before your book is actually published.
There are some smaller trad publishers who do not require the author to have an agent, so rather than querying an agent, your query letter and other submission materials would go directly to the publisher, who may or may not respond to your submission in the following couple of months.
So why go traditional? Because it's traditional. Publishing houses have networks that can, in theory, be leveraged for the benefit of your book because most of them have been in the industry longer than you, even if they're on the smaller side. However, while there might be quite a bit of prestige in trad publishing, you have to be prepared that you might forfeit your ability to have input on the final edits and/or cover design, and depending on your contract as well as how much your book sells, you may not see much by way of monetary profit.
In summary, Traditional publishing has a significant time cost and somewhat of a creative cost as well, but there's a lot of vetted expertise there that has the potential to be advantageous to you if you are prepared to dig in.