Why do People Actually Pay for Prompt Engineering Tools?

I’m currently finishing my CS degree and recently spent some time practicing "Vibe Coding" with Claude Code to build out my portfolio.

I ended up creating an automated prompt optimizer.

Basically, you throw in a messy draft, and it spits out a structured, optimized prompt tailored for LLMs..

It started as a side project for my portfolio, but I was surprised to see quite a few tools in this space charging monthly subscriptions between $5 and $20 for similar functionality.

I’ve tested a few of them, and without trying to sound arrogant, I feel like the logic I built into my free tool actually produces better results.

I’m kept mine free since it was just a "side hustle" to learn the tech, but seeing people charge for this makes me wonder if I’m sitting on something actually valuable.

I'm curious - what do you think actually drives people to pay for these tools, and do you think a project like mine stands a chance at attracting real customers?

(I’m not sure if I can drop the link here without breaking the sub's self-promo rules.
Since the tool is completely free and I’m not making any money off it, I wasn't sure if that changed the rules.
If it’s okay to share it for feedback purposes, please let me know and I’ll edit the link into the post.)