When archery appeared nearly twelve thousand years ago, it seemed to be the natural successor to the atlatl, a weapon discarded by every culture save the Australian Aborigines. The bow and arrow was obviously superior, but not by much. Not to say that archery doesn't have its place; games of skill and organized competitions are immensely enhanced by those proficient with a bow. Hunting is a different story; a sling, spear, or even the classic snare will yield the best results, depending on the game one is after.
Here are three main reasons why archery is impractical.
First, the bow and arrow is difficult to make. Fashioning the bow itself can take up to a year to treat and shape the wood properly, and it doesn't always work. A year could be lost on just one bow if the correct steps aren't taken. I know what you're thinking, the craftsman could make several bows at once, so at the end of the year he'd have a better chance at a properly made weapon. This doesn't make sense when you take into account that the person making the bow would most likely repeat the mistake on each bow, leaving him with who knows how many unusable weapons at the end of the year.
The string for a bow was nearly impossible to make in the ancient world. Catgut or sinew were incredibly difficult to obtain if you weren't in close proximity to the Mediterranean. Hair, hemp, and linens were terrible substitutes, and were very susceptible to moisture and heat. The beeswax needed to guard against the elements was also a very rare item, it could only be purchased or traded for during certain times of year, and at exorbitant cost.
The arrows are an entirely different problem. You need your wood, you need your metal/stone, you need your fletching, all of these things took ungodly amounts of time to collect, make, and assemble. The shaft had to be harvested from a tree that grew very straight branches, shaping one with crooked wood was futile. carving or forging a proper arrowhead took days, and capturing a live bird for the fletching was a task envied by no one. All for one arrow, I might add; If you wanted more, you'd better clear your schedule, because you're in for a long work week.
Second, the bow and arrow is difficult to use (trust me, I've tried.) Pulling back the string alone is nearly impossible if you lack natural core-strength, which most people do, especially in the ancient world. This means years of physical training to build up the necessary muscles to do the job properly, and that means a trainer, as well. Physical training means a proper diet for the best results, the best results means expensive, high quality food. I don't need to tell you that most ancient men weren't rich millionaires who could afford the things needed to become an archer.
Shooting the arrow straight was very difficult, probably more difficult than the fitness regimen required to even have the opportunity to shoot one straight. Shooting an arrow straight required practice, and practice takes time, and time is money, folks. It is possible to self-teach the skills you need to shoot straight, but a trainer would definitely speed up the process. Again, trainers are expensive, unless the trainer was also the one employed to build up your physical strength, then I'm sure something could be worked out. But this is highly unlikely.
Hitting a target is the next step, and it ain't easy. Even if you shoot straight, you have to account for wind and slight body tremors and a million other little factors that will send your shaft reeling. Don't get me started on a moving target. Very few people will accomplish something like hitting a target in motion. Or if you're in motion shooting at a target that's moving. Nearly impossible. Ask the Mongols. And you'd better hope you worked on your stamina with that trainer if you hope to shoot more than one arrow an hour. More time that we can't afford to lose.
Third, archery in warfare just isn't all that practical. Training one man to use a bow and arrow is a tremendous job by itself, training thousands was a joke, and we can't be asked to believe that it was in any way effective when it came to actually hitting and killing an enemy assailant. I know archery was used in ancient warfare, I'm not disputing that, I'm disputing the fact that it was used in any other way than a diversionary tactic. I'll admit It had to be annoying for an advancing army to be bombarded with tiny projectiles constantly while trying to engage the enemy. Most of the shafts probably clattered harmlessly to the ground after deflecting off a soldier's armor. The real danger was slipping on a rolling shaft and losing your footing, and I'm convinced this was the real purpose of the archer in battle.
If both armies had regimens of archers that fired simultaneously, then no doubt at least half of the arrows collided head-on in mid-air, shattering the shafts into splinters. This would lessen the chance of a soldier slipping, but it still most likely came into play to buy a short amount of time.
Archery just didn't make sense, and still doesn't, in my opinion. If you want dinner or to win a war, buy yourself a sling or a spear or a snare. Even a Colt King cobra with a six inch barrel would do the trick. Just don't buy a bow and arrow.