Why some people mow a lawn better than others • Hacker News Board

Re: Why some people mow a lawn better than others

#21

Post by contubernio » Tue, Aug 04, 2026, 7:13 PM UTC

There are a number of bad premises in this article.

For example, most people in the world (outside the USA in particular) have never mowed a lawn. I live in a city of 3.5 million and essentially no one has a lawn.

When you really mow a lawn terrain matters. Most lawns are not flat. One goes on lines of equal height not up and down a hill.

Edges are different than the interior part of the lawn, particularly if they abut flower beds, curbs, etc.

Re passing a given spot is sometimes an efficient way to mow it properly. Particularly in dead ends and odd corners. Etc.

Re: Why some people mow a lawn better than others

#22

Post by doubled112 » Tue, Aug 04, 2026, 7:14 PM UTC

CrzyLngPwd wrote: post #16

Dig that lawn out and start growing food, ffs.

I only have a front lawn (townhouse) and I'm not allowed to plant whatever I want in it.

If somebody reports it, the city can and will come tear it out and charge me for the work.

"Ownership" is a funny thing.

Re: Why some people mow a lawn better than others

#23

Post by stronglikedan » Tue, Aug 04, 2026, 7:14 PM UTC

CrzyLngPwd wrote: post #16

Dig that lawn out and start growing food, ffs.

Why? My dogs and I get much more enjoyment out of a lawn than we would a garden. I can buy food, but space to play fetch is a premium.

Re: Why some people mow a lawn better than others

#24

Post by deweywsu » Tue, Aug 04, 2026, 7:14 PM UTC

gavinray wrote: post #9

Semi-related: Worked as a landscaper during my youth, one of my first jobs I used to think that the line patterns mowed into grass were a purely aesthetic thing. It turns out, the lines are mowed in a rotation to prevent wearing out the grass and causing damage. First you mow length-wise, then width-wise, then diagonally, finally diagonally in the opposite direction, before cycling through again. Useless information…

Absolutely correct. If you always mow in the same direction, the grass always gets pushed in the same way by the lawnmowers blades and it will eventually morph to that direction and lose strength, which appears as grass that doesn't stand straight up, and it looks worse.

Re: Why some people mow a lawn better than others

#25

Post by svat » Tue, Aug 04, 2026, 7:15 PM UTC

This is a really nice presentation of how some people play the authors' lawn-moving game better than others -- a great analysis of the gameplay. But the majority of comments on this HN thread right now are reacting to the title rather than to the article, as if it were about real-life lawn-moving.

Re: Why some people mow a lawn better than others

#26

Post by zahlman » Tue, Aug 04, 2026, 7:16 PM UTC

Dylan16807 wrote: post #15

zahlman wrote: post #8

> You’ve probably done something like mow a lawn or vacuum a rug hundreds of times without thinking much about it. Some part of your brain works out a route that’s usually good enough to get the job done. People are actually pretty good at this, and better than you’d guess for a problem that is hard for computers. We wanted to see it for ourselves, so we built a lawn and asked people to mow it. Is there supposed to b…

> ... If JavaScript is required to view more content than this, why? By "asked people to mow it" they're talking about the visitors to the site. It's interactive. It's somewhat a mistake not to have "skip to results" in the actual html. On the other hand, it makes sense they want to force people to see the landing page first. And unless they want to add a whole rendered fallback the results page isn't going to be sup…

Without JavaScript, there is literally no page text beyond that point until the footer. Thee is no indication that there would be any interactive content. There is also no discussion of what the interactive content demonstrates after it. There are no "results" to which a "skip to results" could skip.

Re: Why some people mow a lawn better than others

#27

Post by sunrunner » Tue, Aug 04, 2026, 7:17 PM UTC

b40d-48b2-979e wrote: post #18

gavinray wrote: post #9

Semi-related: Worked as a landscaper during my youth, one of my first jobs I used to think that the line patterns mowed into grass were a purely aesthetic thing. It turns out, the lines are mowed in a rotation to prevent wearing out the grass and causing damage. First you mow length-wise, then width-wise, then diagonally, finally diagonally in the opposite direction, before cycling through again. Useless information…

wat. Causing damage to the grass you're hitting with a (relatively) blunt object in the first place? All you did was waste three times the gas.

> hitting with a (relatively) blunt object in the first place

Well there's your problem right there.

Re: Why some people mow a lawn better than others

#28

Post by gamerdonkey » Tue, Aug 04, 2026, 7:17 PM UTC

cortesoft wrote: post #3

This is a very different problem than actual efficiency when mowing a lawn or vacuuming a rub. Turning takes more work and time, and you miss a part of the 'square' when you are turning (the arc of the curve is not a straight line). In addition, vacuums especially have an area at the edge of the machine that is not cleaned as well, which is why you want a bit of overlap in your lines. Plus, when mowing a lawn, you of…

This is mentioned in the article when discussing a player that found the optimum route:

> Sarah also did something that appeared a bit unnatural. Instead of simply continuing straight a few times, she intuitively and preemptively turned in a snake-like pattern. This highlighted a key difference between real-life mowing and our simplified game, an approach that strong mowers exploited. Sarah, an avid gamer, seemed to recognize this strategy immediately.

Re: Why some people mow a lawn better than others

#29

Post by collingreen » Tue, Aug 04, 2026, 7:17 PM UTC

b40d-48b2-979e wrote: post #18

gavinray wrote: post #9

Semi-related: Worked as a landscaper during my youth, one of my first jobs I used to think that the line patterns mowed into grass were a purely aesthetic thing. It turns out, the lines are mowed in a rotation to prevent wearing out the grass and causing damage. First you mow length-wise, then width-wise, then diagonally, finally diagonally in the opposite direction, before cycling through again. Useless information…

wat. Causing damage to the grass you're hitting with a (relatively) blunt object in the first place? All you did was waste three times the gas.

I believe the point is the wheel lines and to vary where the wheels go by changing the pattern each time you mow so you don't, for example, always drive exactly down the fence and cause a rut or mulch buildup or missed area.

I dont think it was "don't hurt the grass while you cut it" or "mow it four times in one sitting".

Re: Why some people mow a lawn better than others

#30

Post by altairprime » Tue, Aug 04, 2026, 7:18 PM UTC

scottyah wrote: post #14

cortesoft wrote: post #3

This is a very different problem than actual efficiency when mowing a lawn or vacuuming a rub. Turning takes more work and time, and you miss a part of the 'square' when you are turning (the arc of the curve is not a straight line). In addition, vacuums especially have an area at the edge of the machine that is not cleaned as well, which is why you want a bit of overlap in your lines. Plus, when mowing a lawn, you of…

You should see how optimal the poster's first dates are! Meet at a location with premade bottles of Soylent while they ask 15 questions. Done in 30min. Optimized away the cost and time "wasted" at restaurants or mini-golf type activities.

That’s rather cruel. Optimizing lawn mowing conserves human and machine fuel/battery, especially on large plots or as professionals or in hot climates. Misapplying optimizations to one’s free time is absolutely in line with your stereotype, but that’s much more a widespread defect of judgment in computer engineers than in mowers.