This is hardly the case. I know the submissions process to agents is tough. It’s an uphill email battle that makes you feel alone, sending submissions out into the abyss.
I hate to break it to you, but the submissions and rejection process never really ends.
…Once you get an agent, your agent submits your manuscript or proposal to editors who may or may not connect with it.
…Once you get an editor, your editor submits your manuscript to other authors to get blurbs who may or may not come back with some.
…Once you get your blurbs and the book is finished production, you are submitted for print and online reviews.
The judgment process is never complete, but the good thing is that it’s up to the market (i.e. readers) to determine if your book is going to be successful.
Write for them. Write for your audience.
They’re the ones that will pre-order your book, request it in bookstores, and the ones that will support you on social media. They’re the ones that will determine how successful your career is going to be. Agents invest their time in you and help shape the direction of your career, editors refine the product and get it ready for production, and publicists and marketers make people know it’s available, but the readers will show with their wallets how much they support you.
You are in charge of your own sales track record–the only thing that will give you leverage–so write for them and show them you have staying power.