#state machine

It's absolutely a programming oversight. The vast majority of the time, the player wants to do one single action at a time - navigate the UI, perform some kind of action, move somewhere, etc. When we allow for multiple actions to occur simultaneously, the player can end up in situations they did not expect nor desire due to the simultaneous actions.

Remember, when it comes to dealing with edge cases we developers live in a land of worst-case scenarios. The worst case scenario in this case is that the player can accidentally break the game state while in such a situation. The player could get into a fight that they did not intend, fall off a ledge, consume a critical or valuable item, or any of a thousand other problems. We have to consider how damaging to the player experience the issue might be. Obviously, a broken game state is a lot worse experience than an errant extra jump input as the player returns to gameplay. This is usually why we completely disable normal inputs during UI menu navigation - so that the player will remain in the exact same position for the duration of the menu navigation, even if the rest of the game world continues to update (e.g. in a multiplayer game) and behave normally.

Readers may recall my post on [ladders] and notice some parallels between the state transitions here. That is:

Ladder : UI Menu

Regular Gameplay : Regular Gameplay

Get Onto the Ladder : Transition from Gameplay to Menu

Climb up/down the Ladder : Navigate the Menu

Get Off of the Ladder : Transition from Menu to Gameplay

It is during these transition stages that a lot of bugs can occur if we do not properly clean up the state we're leaving and set up the new state we are entering. If you see misbehaving inputs like the ones you asked about, it is usually because of these state transition cleanup issues.

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all hail the wonderful state machine

I suspect it’s because of how a lot of gameplay is defined as a “state machine”. A state machine basically means that the player is always in some pre-defined state, with specific transitions out of and into those states based on input and factors. For example, in a really basic version of Super Mario Bros, you might have defined states like standing, walking, jumping, falling, and dying. Depending on the inputs, Mario transitions from one state to another. Here’s an example:

In this simple state machine, Mario cannot land from a jump in the walking state. He can only land, stand for a moment, then begin walking. Mario cannot directly transition from walk to neutral jump, Mario must stop walking and transition to the stand state before he can neutral jump. Similarly, Mario cannot go from standing to forward jump, Mario can only jump forward while walking. This enforces certain limitations, like Mario not being able to jump again until he lands on the ground.

Here’s the thing about these state transitions - they often require playing some sort of animation and require at least one frame of processing before they can change state again, because the system is handling the transition to this state on this frame. I suspect this is why, in Super Mario Bros, you can jump off of certain things on the first frame you land on them - you’ve stopped falling for one frame and are in the “standing” state, which allows for jumps. The second frame in, the terrain Mario was standing on is no longer there so Mario transitions from the standing state back to falling and can no longer jump. But it was for that one frame, so a player with good timing can 1-frame jump off of it.

State machines are a super common tool used for controlling gameplay because we naturally want to limit what the player can do in each state. One-frame state transitions tend to be fine for most players thanks to the difficult timing windows involved. Speed runners push those limits far beyond what we normally expect players to do, but they are also generally not the target audience for our games so it doesn’t make a huge difference to the developers if they can take advantage of them, as long as it doesn’t cause other players grief when players do so. Sometimes frame-perfect tricks are even supported by the game in order to reward better play, like fighting games.

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The startup space is filled with acronyms and ratios. Out of context and without any understanding of their effects, it is easy to get lost or focused on the wrong things for your current situation. In episode 994 of This Week in Startups, All Turtles CEO Phil Libin goes through his “Growth State Machine.”  This state machine is meant to help you visualize the flow chart your customers go through and what KPIs you should be tracking for each step and what ratios actually matter and how to create your own ratios. For a full explanation of this Growth State Machine, it starts at the 3:26min mark (https://youtu.be/UjyhDOb_j1I?t=206).  The big take away is that this gives a solid framework to map out the overall going to market strategy and to then even do things like create teams or focus on certain transition lines that are important for the situation your startup is in.

For some tips and deeper explanation on the states and transitions, start at the 13:26min mark(https://youtu.be/UjyhDOb_j1I?t=806). An interesting takeaway is that most startups focus on transition line 1 as this is where most of the tools and conversations are centered around, but this is usually not the place that has the most impact when you are starting out.  For instance, the things that affect line 1 are the typical Sales and Marketing with tools like PR, SEO, Word of Mouth, Channel, Etc. These are the easiest thing to wrap your head around and the easiest to throw money at and track with ratios and KPIs.

Though as a startup, the transition line that has the most impact on success is line 2. Line 2 is when first-time users transition to inactive users, having a high “Bounce”, is essentially saying you enjoy throwing money away since all of the money you spend on getting users to your product is waste since no one stays long enough for you to return your investment in getting them. In typical acronyms, your CAC to LTV ratio will be terrible as you will spend money getting people to your product and have a very low customer LTV as your customers don’t stay long enough for you to get any value from them. 

So now let's use the state machine to help guide a decision on how to spend money and where. You can see the path your users are taking, thus, the point of line 1 is not to focus on your CAC and LTV, but for where they go. With the focus on line 2, your goal for line 1 is actually to get enough users to be able to measure and get statistically meaningful data on how to improve line 2 and reduce your bounce. So once you get enough users to get statistically meaningful data on line 2, you can shift your focus and spending to line 2 and make sure your bounce is healthy.  

As a bonus, something else that should be clarified is that retention is the combination of both bounce (lin 2) and churn (line 8 and line10). This clarification is important since the reason people bounce and churn are very different, and if you are only measuring retention, you really can’t make clear judgment calls on the tests you are running. 

Hope this helps, and definitely watch the rest of the segment in this episode to hear Phil go through more of the chart and how to use it.