“Starting well doesn't mean succeeding.”
Original
Začít dobře neznamená uspět.
Related quotes

Quoted in: Kabir, Hajara Muhammad (2010). Northern women development. [Nigeria]. ISBN 978-978-906-469-4. OCLC 890820657.

“Christianity may well have succeeded even if Constantine had not converted.”
Introduction
The Triumph of Christianity (2018)

“Something doesn't start
at its usual time.
Something doesn't happen
as it should.”
"Cat in an Empty Apartment"
Poems New and Collected (1998), The End and the Beginning (1993)
Context: Something doesn't start
at its usual time.
Something doesn't happen
as it should.
Someone was always, always here,
then suddenly disappeared
and stubbornly stays disappeared.

Source: António Costa (2022) cited in: " Portugal election: Socialists win unexpected majority https://www.bbc.com/news/entertainment-arts-60194375" in BBC News, 31 January 2022.