People think the Yugo was a horrible car - they keep forgetting that it cost $4000 when the average car sold in the U.S. cost $11,000 - you get what you pay for! For $4000 it was not a bad car - certainly not any worse than the 1986 Hyundai that cost exactly $1000 more! - but you don't hear about how bad those were very often.
I know somebody who had one for 180,000 miles - then it was rolled and totalled on the highway.
They earned a reputation for being unreliable because owners neglected to have the timing belt replaced at 30,000 miles - when it snapped the engine was ruined. So no - the Yugo wasn't unreliable - just poorly maintained by most.
One thing though - it is CHEAP! - and I mean that as in poor fit and finish cheap - but then again no worse than the more expensive 1986 hyundai.