Townshend wrote the song during the summer of 1965, and the band recorded it consistently with his home demos. According to Townshend, the song "wasn't as good as this before I did it with Keith [Moon]. It's not my favourite one on the LP. It reminds me a bit of Sandie Shaw." Chris Charlesworth calls the melody "attractive." Charlesworth particularly highlights Moon's unusual drumming, in which Moon uses only his tom-toms during the verses and refrain and incorporates cymbals only for the bridge and the solo.Allmusic critic Richie Unterberger calls it one of the "highlights" of My Generation. But Steve Grantley and Alan G. Parkerdescribe the song as being "so-so" and "pretty conventional." But they too acknowledge the power of Moon's "intermittent controlled" drum patterns and remark that it contains a preview of some elements of later Who songs, such as Townshend's "tentative crash chords." Who biographer John Atkins concurs that the song is rather conventional and describes it as a "straight pop song."

Nicky Hopkins joins the band on piano for the song, and author Mike Segretto claims that his "hyper piano runs contribute much amphetamine fuel to it. Segretto also believes that the "shuffling rhythm" was influenced by Martha and the Vandellas' "Heat Wave." Segretto claims that like "The Kids Are Alright," also from My Generation, "La-La-La-Lies" "transform[s] the romantic song into something defiant," in this case by declaring that his love is strong enough to withstand the "slander of jealous parties."

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