Compare implementing a simple automation design on a MCU vs an FPGA/CPLD
There's no reason to use FPGAs unless you need to.  Even two similarly talented engineers in the MCU and FPGA fields would use an MCU for a relatively simple automation task.

Pro MCU:


MCUs usually have all the peripherals to the outside world ready to go
Compiling takes seconds (FPGAs take minutes to hours)
There are an order of magnitude (or two!) more engineers that can help, or pick up where you left off. (For a fun, not necessarily statistically valid, comparison - compare the number of Q&amp;A on Stack Overflow for C vs VHDL or FPGA)


Use an FPGA if you have to because:


The number-crunching required can't be met in the power, weight, size or cost budget with a microprocessor
There are hard real-time deadlines which can't be guaranteed with software (response times in the microsecond realm for example)
Using FPGA logic may make it easier to make robust assertions about response times
You can make big savings in cost, power etc by using custom data-types (like a 12-bit floating-point for example)


Or:


Your assignment tells you you have to :)