Version 1:  (source)

There once was a speedy hare who bragged about how fast he could run. Tired
of hearing him boast, Slow and Steady, the tortoise, challenged him to a race.
All the animals in the forest gathered to watch.

Hare ran down the road for a while and then and paused to rest. He looked
back at Slow and Steady and cried out, “How do you expect to win this race when
you are walking along at your slow, slow pace?”

Hare stretched himself out alongside the road and fell asleep, thinking,
“There is plenty of time to relax.”

Slow and Steady walked and walked. He never, ever stopped until he came to
the finish line.

The animals who were watching cheered so loudly for Tortoise, they woke up
Hare.

Hare stretched and yawned and began to run again, but it was too late.
Tortoise was over the line.

After that, Hare always reminded himself, “Don’t brag about your lightning
pace, for Slow and Steady won the race!”

Version 2.  (source)

Lord Dunsany brings out another view in his satirical “The True Tale of the Tortoise and the Hare”. In it the hare realises the stupidity of the challenge and refuses to proceed any further. The obstinate Tortoise continues to the finishing line and is proclaimed the swiftest by his backers.

But, continues Dunsaney, the reason that this version of the race is not widely known is that very few of those that witnessed it survived the great forest-fire that happened shortly after. It came up over the weald by night with a great wind. The Hare and the Tortoise and a very few of the beasts saw it far off from a high bare hill that was at the edge of the trees, and they hurriedly called a meeting to decide what messenger they should send to warn the beasts in the forest. They sent the Tortoise.

Version 3  (Argh!)

Hare and Tortoise both take team-building personalities surveys which gently reveal their individual strengths and weaknesses.   Their big breakthrough comes when they figure out that they BOTH have BOTH–strengths and weaknesses!

With that out on the table they started letting go of their defensive fears.  Soon they realize that they don’t have to prove anything anymore about winning or losing and strengths or weaknesses.

With great relief  they start brainstorming how they can help each other instead of trying to outdo one other.

Soon they form a new fast and reliable delivery company, “Tortoise and Hare, Inc.”  with the musical jingle
“We sprint at a steady pace!  Making sure your package wins the race!  Nah Nah Nah Nah, Nah Nah Nah Nah, Hey Hey Hey, Good-bye!”   (Just sing the first half over the Nah Nah Nah stuff and you’ll have a great time! Argh!)