There's enough evidence to believe laziness is, at least partly, a consequence of bad genetics (https://www.youtube.com/watch?v=gd7wAithl7I, with sources in the description), similarly to what differentiates early risers and night owls.

Not saying one should use this as an excuse but being aware of it will at least make you stop obsessing about why you're so damn lazy. Just embrace it and (ironically enough) take it easy.