itch.io

I've done a few more than 3 jams the last few years, normally 1 every few months, and I still get caught short on scope and timing.

I think it might be because I'm always trying to do something new and different.  When trying out new things, I can never really predict how long it will take, how much work will be involved or even what the final product might look like.  I'm not too bad at guessing how long the complex or new bits might take, it tends to be underestimating how long it will take to do all the rest to a reasonable quality.