What is it that secures a place in history? What is it that secures longevity for an artist? Fashions come and fashions go, but some live on while others are forgotten.
Quality, of course, has much to do with it. Not quite everything though, or we'd still be familiar with the music of Ignaz Pleyel.
'Ignaz who?' I hear you asking. It's a famous name, but one that passes us by.
He was as big in his day as another man of those years who needs no introduction - Franz Joseph Haydn.
Haydn was Pleyel's teacher. Ignaz was in his teens when he was sent to Eisenstadt, the seat of the Esterházys, where Haydn was the composer-in-residence, to learn from the great man. Haydn rated his pupil. In fact, there's some music now attributed to Haydn that was in all probability written by Pleyel. Such are the tricks that history plays.
The two of them duly went their separate ways, but their paths crossed frequently, and they became friends. When they both ended up in London, that friendship deepened. They'd dine together and go to each other's concerts.
Pleyel's music was as highly thought of as the output of the prolific Viennese.
He was hugely popular, writing material that was very much in keeping with the time - engaging, melodious. Bright symphonies and concertos, and pieces for smaller ensembles. He got great reviews in the fledgling press.
This, remember, was when Mozart was in his pomp, and Beethoven and Schubert were on the scene too. Pleyel held his own. He was a favourite of the contemporary English novelist, Jane Austen.
His spell in London made him a very wealthy man. Eventually, he settled in Paris and moved into the business end of music. He set up a publishing house and opened a piano factory.
This was when the instrument was evolving from the rather one-dimensional fortepiano that harked back to the harpsichord - all a bit wooden, a bit honky-tonk, but very evocative nonetheless - into a musical medium capable of exploring the full spectrum of emotions.
Pleyel's pianos had metal frames, which gave them the stability to let the strings resound. He was also a musical evangelist. He was the one who created the less expensive upright version.
The name Pleyel above the keyboard meant something, like Bechstein, Blüthner, Bösendorfer, or Steinway. He supplied instruments for Chopin, and many other top pianists.
The business lasted for more than two centuries before competition from the Far East forced its closure just last year.
You'll also see the family name above the door of the Salle Pleyel, one of the principal concert venues in Paris, just down the Rue du Faubourg St-Honoré from the Élysée, the Presidential Palace.
In terms of the classical playlist, Ignaz Pleyel may have faded from view. But a little investigation will turn up a lot that is very listenable. And his name - on those pianos and that concert hall - tells you that he was a significant player… and maybe should be still.
George Hamilton presents The Hamilton Scores on RTÉ lyric fm from 10am each Saturday morning.