Can you fail in Disco Elysium? The answer depends on what kind of failure you have in mind. The game's countless RNG checks mean failure in inevitable at some point, and you're probably going to die more times than you want. However, it's almost impossible to lock yourself out of progressing the case. Here's what happens if you do fail and what it means for your progress.
Disco Elysium Checks Explained
Disco Elysium has two kinds of checks, red and white. These pop up at key moments relevant to the plot, a quest, or your relationship with a specific character and rely both on your proficiency in a given skill area and a random number generator.
White checks are more common and give you multiple chances to pass - but not all at once. Red checks are usually related to the plot and only give you one chance to pass. There's no way to reset red checks.
Whatever the type, each check requires a dice roll. You roll two six-sided dice, and the necessary numbers range from 6 to 20 depending on the check type, such as Trivial or Legendary. Your skill numbers are added to the roll number - unless it's snake eyes (two 1s) which is an automatic fail - though equipment and other factors can influence checks as well.
Failed a Check in Disco Elysium
Failing a check is bound to happen, even if you plan your skills well. However, it's also supposed to happen. Failing a white check requires you to either level up a specific skill to try again or, sometimes, speak with the right person to get another chance.
Failing a red check also doesn't lock your progress, though it might block you from accessing a certain questline or developing a relationship further. In other cases, you just need to find a different approach to solving the problem.
You can technically build Harry in such a way that you soft lock the game at certain points. However, it's hard to do, and you have to go out of your way to make it happen. Most areas of Disco Elysium have enough items or quests where you can build up the necessary skill and have a decent chance of accomplishing certain tasks or passing important checks anyway.
Run out of Time in Disco Elysium
You have 10 in-game days to solve the mystery in Revachol. That's more than enough time to gather clues and determine who the killer is, and it's also impossible not to reach the ending (unless you die, of course). There's only one proper ending in Disco Elysium, though how the final scenes play out changes depending on whether you meet certain requirements.
If, at the end, you lack what you need to pass the final check and speak with two crucial characters on the island, you're just prompted to restart earlier and try again. There's no ultimate fail state.
While it's not part of the ending, there's also a hidden path you can help Cuno on if you work to develop your relationship with the ne'er-do-well. Spending time in the thought cabinet will help Harry grow further in the way you want him to, and while time doesn't pass when you walk around, fast travel certainly makes mobility more convenient.