Short answer: instead of checking Amazon and Goodreads by hand every week, use an RSS feed (Goodreads offers one natively) or a scheduled search, and connect it to n8n or Make so every new review saves itself into a spreadsheet with date, platform, and rating.
Reviews are the social proof a new reader checks before buying. Knowing how many you have, on which platform, and at what rating, without manually visiting each site, saves time and gives you a clear view of how the book is doing.
Amazon doesn't offer an official reviews RSS feed, so the realistic alternative is checking manually every 1-2 weeks, or using a page-monitoring service that emails you when the page changes — not as fully automated as Goodreads, but it cuts down on daily checking.