This is a difficulty mod. This makes the game slightly harder for those seeking a challenge. That said, this mod is designed for an accelerated start with robots.
Machines require maintenance. They'll occasionally stop working and need to be serviced. If you have bots, they'll automatically replace them. You'll need to build a refurbisher to restore the removed machine to working order. Damaged machines are checked additionally and have a higher chance of breaking the more damaged they are. Miners also break when they run out of resources, requiring maintenance before they can be re-used. Machines that require maintenance are assemblers (all tiers), chemical plants, oil refineries, centrifuges, steam engines, turbines, labs, and modded entities that perform these functions.
In normal mode, simply refurbishing them is all that's needed. In hard mode, refurbishing restores most of the ingredients and it needs to be reassembled.
Assembler Assay also includes a Foundation option where machines (except mining-drills) take damage if they lack a proper foundation. Which in turn can cause them to malfunction sooner! Machines are half as likely to take damage if they're on brick and they take half as much damage. Both of these are halved again for concrete! Machines on refined concrete take no damage. Concreep is heavily recommended when playing with this option turned on.
Pollution clogging is an additional option where machines have an increased chance to fail in heavily polluted areas.