What would be a reason for recommending Great Expectations?

The only way to answer this question is to quote from the book in order to show the appeal of Charles Dickens' writing. The best example of his writing to be found anywhere in all his extensive works is Chapter 39 of Great Expectations. Characteristically, he opens his chapter with a passage of description to set the place and mood of the scene. The description may be of the interior of a room, or of the weather outside, or of an individual character. In Chapter 39 he begins, quite appropriately, with a description of the stormy night out of which the excepted convict emerges like a ghost of the past.

It was wretched weather; stormy and wet, stormy and wet; mud, mud, mud, deep in all the streets. Day after day, a vast heavy veil had been driving over London from the East, and it drove still, as if in the East there were an eternity of cloud and wind. So furious had been the gusts, that high buildings in town had had the lead stripped off their roofs; and in the country, trees had been torn up, and sails of windmills carried away; and gloomy accounts had come in from the coast, of shipwreck and death. Violent blasts of rain had accompanied these rages of wind, and the day just closed as I sat down to read had been the worst of all. 

In the next paragraph Pip adds further description of the violent storm:

I saw that the lamps in the court were blown out, and that the lamps on the bridges and the shore were shuddering, and that the coal fires in barges on the river were being carried away before the wind like red-hot splashes in the rain.

Many modern readers are impatient and skip descriptions in order to get on with the story, but they are missing some of the best Dickens has to offer. People had more patience in Victorian times because there were so few alternatives for leisure-time recreation. Charles Dickens himself read his works on the stage in England and America for many years. Audiences loved to hear him recite such passages as those quoted above. His descriptions are almost like Impressionistic paintings. Note the vivid image conveyed by the line:

...coal fires in barges on the river were being carried away before the wind like red-hot splashes in the rain.

But this is only the beginning. From out of the distant past Abel Magwitch appears. He seems totally indifferent to the storm because of the life he has lived in England and in far-off Australia. He is there to destroy all of Pip's illusions and to claim him as his foster son. Pip has become a gentleman, and the storm means little to him because he is seated in a comfortable chair, reading a good book in front of a blazing fireplace. He realizes not only how his own comfort and security have depended on the privations and suffering of a lower-class man, but how all ladies and gentlemen of the leisure class are equally helpless, and useless, without the support of the men and women they consider far beneath them.

The dialogue in Chapter 39 is simply marvelous. Stephen Leacock compared Dickens to Shakespeare in Charles Dickens: His Life and Work (1933). Here is one of the best examples of dialogue from Great Expectations:

“Yes, Pip, dear boy, I've made a gentleman on you! It's me wot has done it! I swore that time, sure as ever I earned a guinea, that guinea should go to you. I swore arterwards, sure as ever I spec'lated and got rich, you should get rich. I lived rough, that you should live smooth; I worked hard that you should be above work. I tell it, fur you to know as that there hunted dunghill dog wot you kep life in, got his head so high that he could make a gentleman—and, Pip, you're him!”

Pip knows he was only motivated by fear when he brought the vittles and the file to the convict on the marshes. But Abel Magwitch has experienced so little human kindness that he remembers it all his life. The poor man thinks that a gentleman is the finest specimen of humanity and is proud that he has created one by himself. But Pip knows from his own example that a gentleman is all show and no substance. He is living on the hard-earned money of another man who not only thinks that he acted "nobly" there on the marshes, but that he has become an even more noble person with his fine clothes, fine manners, fine lodging, esoteric books, and perfect command of the King's English. Pip is thoroughly humiliated and has all his dreams destroyed in this magnificent chapter by the great Charles Dickens.