Tutorials are universally terrible. I feel like I've been writing this for years, but they remain the single largest obstacle to games growing in popularity, and as someone who has been playing games for decades, their tedium still regularly turns me away from something new within an hour.
And don't kid yourself: it's not because games are complicated.
There is no reason that your grandparents shouldn't be able to pick up and learn how to play Crusader Kings 2. The reason they can't or don't isn't that the game is fundamentally too complex for them to fathom. It's that it does such a poor job of introducing its systems and concepts - and historically, all games have done such a poor job - that there is an artificial barrier to entry which puts them off from trying.
Increasingly, I feel the same way. Fiddly controls and obtuse interfaces and the terrible bore of being taught how to play makes me want to switch the game off and go do something else. I know how to play Crusader Kings 2 already - which is a fine game, and which I do not mean to single out for special criticism - but often when sitting down to play something new in a genre I'm already familiar with I find myself giving up almost immediately. I no longer have the time or inclination to bash my head against Planet Coaster till it reveals its secrets to me. I just want to build rollercoasters and now.
The problem, to me, is that we have the concept of tutorial modes or levels. Nobody wants, before they play a game, to play a shit version of that same game where they can only do what on-screen text prompts tell them to do. Nobody wants to be hemmed-in like that; no one wants to read the text or listen to the voice actor; no one wants to skip the "play game" button for something tangential. No one wants to sit a test before watching a film, or listen to a lecture before reading a book. Games should teach you to play them while you play them, and offer enough to the player that they're still able to have fun in the process.
That ought to mean more than just tooltips, too. Every game should be designed with the assumption that the audience has never played a game before. It should be built from first principles around the experience of learning how to play it. This means that if your game begins with sixteen different interface elements and eight buttons along the bottom of the screen, you've already failed.
Don't show me what I need to learn until you're ready to explain how it works. Introduce your game to me as you would explain it to a friend you were trying to convince it was cool and exciting as much as teach them how to play. If I become excited or interested in one element as you introduce it, let me follow that interest for a while and advance to something new only when I'm ready rather than railroad me down a prescribed path. If I already know how to play, give me an option to skip all of this, of course, but make your difficulty levels more granular and descriptive than easy-normal-hard. If you do have an easy preset, make it easier to learn, not just easier to win.
Stop forgetting to make tutorials and stop making tutorials. Start making games for human beings.