When you have put together hundreds of chemical solutions to do the same experiment for each one with repeat readings for each, all having to be done manually, requiring no let up in concentration and taking from 8am through to 9pm without anything but short breaks and taking many weeks to complete - then come back and tell me the process isn't boring!  

I far preferred working in a factory because I could do my tasks without thinking about them which left my brain free to wander to more interesting things.

I suppose that any chosen career will have it's dull periods though.