Apart from the hiss and the echoey print-through and the penchant for getting 50 feet of tape wrapped impossibly around the innards of the deck, they often suffered badly from wow and (especially) flutter, especially if you were trying to listen to piano or clarinet music. Then there was all that brown gunge on the heads and the little rubber wheel and the need to degauss the heads...

They had their place. But, as technology, they were right down there with low energy fluoresent light bulbs...