Latin has a bad rap nowadays. Actually it's had a bad rap for a while. It is stuffy. Archaic. Blah blah blah. I won't take aim at those paltry objections here, since I pity–and endure–modern man's alienation from his past. To one accusation, however, I strenuously object, and that accusation is of Latin's peculiar difficulty. Yes, the process of learning Latin has challenges, but far fewer than of learning languages like Greek or English, and no more than many other endeavors. Unlike the problem of learning the subtleties and seemingly endless variations of English, the difficulties in learning Latin, at least for the native speaker of English, are few and predictable. In my years teaching, they are the ten which follow. Additions welcome.
10. Ignoring the Part of Speech
One of the struggles I least expected was how unfamiliar some students are with the parts of speech: noun, verb, adverb, et cetera. Even having overcome this difficulty, I still have ripped hairs from my head trying to help students limit the function of words to what they are categorically able to do. Chiefly, this problem applies to comprehending verbs. For example, many times students define vultis, as "wish," which is all well and good excepting that in English, wish can be a noun or a verb. Similarly, many students try to determine case and use of adverbs, such as paulisper, "for a short time," since they seem often to conform to the case uses, ignoring that their part of speech makes such unnecessary and impossible. The problem is harder to overcome when explaining compound forms such as infinitives, participles, and gerunds.
9. Vocabulary and Broad Meanings
While every Latin teacher has to cope with students who don't diligently study vocabulary, more challenging is getting them to memorize the fully entry, and harder still to use that information. It is one thing to know that manus means "hand," another thing to realize it uses fourth declension endings, and still another to know its gender is feminine and therefore must agree with a feminine adjective. Likewise it is easier to know that pono means "put" than it is to know all of its principal parts by which to conjugate and recognize its forms in all tenses, persons, numbers, and voices. Even students who memorize their vocabulary, though, often struggle at calling them to mind as they read and using the information of the entry to identify the form in from of them.
Post equitem sedet atra cura.Horace's line has been infamously mistranslated by Latin neophytes as, "The black lady sits cautiously behind the horseman," instead of "Black care sits behind the rider."
8. Brute Force Memorization

For example, it is one thing to remember that nomine may mean "named," because it is commonly seen as such, at least in some text books, but another to realize it is used in the ablative case to mean "with respect to name." This recall may simply look like experience, and it is in fact useful and as far as some students get in their understanding, but it is not proficiency. Such recall is commendable if it proceeds along with and feeds grammatical understanding, but alone is illusory understanding.
7. Heuristics

6. The Inflection Hump

You can put a subject and object next to one another as in Marcus manum and you'll get "Marcus' hand." Likewise some students default to making proper nouns the subject, so if you put lupus Marcum terret, you will most certainly get as a translation, "Marcus scares the wolf."