What the 125°C rating buys you
The STM32L053R8T3: That means it can sit on a motor drive board next to a hot IGBT heatsink or live in an engine-bay ECU without derating.
Memory and analog — what's on the die
The 2 KB of EEPROM on-chip is a genuine differentiator: you can store calibration constants, serial numbers, or configuration parameters without adding an external 25LCxxx part, which saves board space and one SPI bus. The 16-channel 12-bit ADC and single 12-bit DAC cover most sensor-input and analog-output needs for a control loop or data-acquisition front end. If your design needs more than 51 GPIOs, you'll need to step up to a larger package variant.
Peripherals and connectivity
The internal oscillator means you can skip the external crystal if the timing accuracy requirements are loose, but for USB operation you'll still want a resonator or external clock.
Package and footprint
Housed in a 64-LQFP (10x10 mm) with a 0.5 mm pitch, this is a hand-solderable package if you have a steady hand and a fine tip. The surface-mount footprint is standard for two-layer boards; no hidden thermal pad to worry about.
Lifecycle and supply
ST continues to manufacture the STM32L0 family, and the STM32L053R8T3 remains a current catalog item.