A natural sense of discovery is essential and needs to be protected at any level of user experience. It's not a good idea to force people into flows they didn't choose.
The type of a Guide, the way it displays, and the limits such as click restrictions on the page will all define the level of interference you create for your end-users.
For Guides that are automatically triggered, we strongly recommend using the Quit Icon at the first step so people can exit the tour if they want to. Locking them inside the tour until they finish it will only create frustration.
Besides, asking whether they want to take a tour in the first step will lead to much better completion and satisfaction rates. Here, you can use Call-to-Action Buttons.
You can also use softer dismiss options (e.g., "Later") and provide them an option to start the tour again.
If you activate a Hotspot or a Checklist for end-users, you give them an option to start and walkthrough (formerly dismissed) Guides when convenient for them.