We learn more quickly and bring back to mind more readily
The things we laugh at than those we respect and revere.

[Discit enim citius, meminitque libentius ilud
Quod quis deridet, quam quod probat et veneratur.]

Horace (65–8 BC) Roman poet, satirist, soldier, politician [Quintus Horatius Flaccus]

Epistles [Epistularum, Letters], Book 2, ep. 1 “To Augustus,” l. 262ff (2.1.262-263) (14 BC) [tr. Palmer Bovie (1959)]
    (Source)

On why he declines to write epic poetry: because he doubts his talents, and the public will remember only if it's a bad poem. Which is especially problematic if the poem is about someone (like Augustus) still alive.

(Source (Latin)). Other translations:

A man may soner beare awaye and rather kepe in mynde
The thinge deryded, then that is prayse worthie in his kynde.
[tr. Drant (1567)]

For Readers so malicious now are growne,
What's bad they'll con, what's good they let alone.
[tr. W. P.; ed. Brome (1666)]

For what's derided by the Censuring Crowd,
Is thought on more than what is just and Good.
[tr. Creech (1684)]

For quickly we discern,
With ease remember, and with pleasure learn,
Whate'er may ridicule and laughter move,
Not what deserves our best esteem and love.
[tr. Francis (1747)]

For sooner caught and steadier to abide
On memory's tablet that which we deride,
Than what revere.
[tr. Howes (1845)]

For one learns sooner, and more willingly remembers, that which a man derides, than that which he approves and venerates.
[tr. Smart/Buckley (1853)]

For easier 'tis to learn and recollect
What moves derision than what claims respect.
[tr. Conington (1874)]

For we learn quicker, gladlier recollect
What makes us laugh, than what commands respect.
[tr. Martin (1881)]

The subject of our zeal sooner hears of, and is more inclined to remember, that which any one laughs at in the production than what he approves of and eulogizes.
[tr. Elgood (1893)]

For a man learns more quickly and remembers more easily that which he laughs at, than that which he approves and reveres.
[E.g. (1907)]

For one sooner learns
And easier remembers such concerns
As men deride that those men favor lend
And venerate.
[tr. A. F. Murison (1931); ed. Kramer, Jr. (1936)]

For we all more quickly learn and easily remember
the poems we scorn than those we approve of and respect.
[tr. Fuchs (1977)]

And writers of foolish poems often find
They're vividly and scornfully remembered.
[tr. Ferry (2001)]

For a thing that causes merriment is always sooner learnt
and longer remembered than what commands respect and approval.
[tr. Rudd (2005 ed.)]

Men remember more quickly, with greater readiness,
Things they deride, than those they approve and respect.
[tr. Kline (2015)]