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Explain xkcd: It's 'cause you're dumb.
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I'll never install a smart home smoke detector. It's not that I don't trust the software--it's that all software eventually becomes email, and I know how I am with email.
Title text: I'll never install a smart home smoke detector. It's not that I don't trust the software--it's that all software eventually becomes email, and I know how I am with email.


Cueball has an unspecified communication application on his phone. As the chart displays, the longer he has the app, the more unread messages he has on it (likely due to a combination of more people trying to contact him over it and him checking it less diligently). Eventually, he gives up reading every message, and he notices apathetically when it reaches 10,000 notifications. The joke comes in the caption, which states that all communication services have this problem and implies that this problem is the key problem with email.

The caption, "Another way every system eventually becomes email" (emphasis added) is a reference to Zawinski's law of of software envelopment: "Every program attempts to expand until it can read mail. Those programs which cannot so expand are replaced by ones which can." In this case, it's not that every program will eventually become capable of sending and receiving emails, but rather that Cueball/Randall will treat every program that provides notifications the same way he treats his email inbox.

In the title text, Randall uses this reasoning to explain why he'll never install a smart smoke detector. A smart detector would send a notification to his phone when the smoke level is high enough to trigger it, or perhaps when it is running low on battery; following the same trend, Randall believes he will eventually stop reading the alerts from the smoke detector. Ignoring a smoke detector is dangerous.[citation needed]

Randall has previously covered his trouble keeping up with email, for example in 1783: Emails.


[A graph with the x-axis and y-axis labeled]
[The graph has a line that starts near the bottom of the x-axis, fluctuates a little, then steadily increases until it is approaching the maximum of the y-axis, whereby it begins to level out]
Percentage of received messages in the service that are marked unread
Time --->
[Three Cueballs standing at different points on the graph. The first two are shown directly above the line at the beginning and middle areas, and the third is shown below it near the end of the graph. All three are holding phones.]
[The first Cueball looks at his phone, which displays two notifications on an app]
Oh hey, two new messages!
[The next Cueball again looks at his phone, this time with 45 notifications on the app]
Ugh, gotta take some time to go through these.
[The last Cueball's phone app shows 10129 notifications]
Wow, it hit five digits.
[Caption below the panel]
Another way every system eventually becomes email

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