As someone who's worked in the online advertising industry for years, I can attest to the fact that it's not an easy field. There are constant changes in the algorithms used by the major search engines, new ad platforms popping up all the time, and a never-ending arms race to get the most clicks (and conversions) at the lowest cost.

That's why I always recommend businesses use a digital marketing agency to handle their online advertising. Yes, it's an additional expense, but it's worth it for the peace of mind and results in you'll get from having professionals handle it (most of the time a good agency will lower wasted ad spend and be worth their weight in gold) .

Here are a few more specific reasons why online advertising is so difficult:

1. The Search Engines Keep Changing Their Algorithms

This is probably the number one reason why online advertising is tough. Just when you think you've got a handle on things, Google or Bing or Yahoo goes and updates their algorithms, and everything changes.

For example, a few years ago Google introduced "Exact Match" as a keyword match type, which changed the way many people ran their campaigns. Then, earlier this year, Google made another change to how exact match works. And these are just two of the many algorithm updates that have happened in recent years.(if your ad campaigns are still using broad match you're in for a world of hurt)

2. There are So Many Different Ad Platforms

Not only do businesses have to worry about the major search engines changing their algorithms, but there are also a ton of different ad platforms out there. Google has AdWords, Bing has Ads, Facebook has Ads, Twitter has Promoted Tweets, and the list goes on.

And each of these platforms has its own quirks and features that you need to learn in order to be successful. For example, Facebook Ads are great for building brand awareness, but they're not so good for driving direct sales. Twitter Promoted Tweets can be very effective if used correctly, but they're also very easy to waste a lot of money on if you don't know what you're doing.

3. The Cost of Clicks is Constantly Going Up

As more and more businesses start to realize the power of online advertising, the cost of clicks is going up. This is especially true for popular keywords in competitive industries.

For example, a few years ago you could get click on the keyword "insurance" for a few cents. Nowadays, that same click will cost you a dollar or more. And if you're in a competitive industry, like travel or eCommerce, you can expect to pay even more per click.

4. There's a Lot of Wasted Ad Spend

Another big reason why online advertising is so hard is that there's a lot of wasted ad spend. This is often due to poor campaign management or incorrect targeting.

For example, if you're targeting the wrong keywords, you'll end up paying for a lot of clicks from people who are not interested in what you're selling. Or, if you're not monitoring your campaigns closely, you might end up paying for a lot of clicks from bots or fake accounts.

5. It's Easy to Get Stuck in a Rut

Finally, it's easy to get stuck in a rut when you're running online advertising campaigns. This is often because you're relying on the same tactics and strategies that you've always used.

For example, if you're used to running Google AdWords campaigns, it can be tough to switch to a new platform like Facebook Ads. Or, if you're used to running display ads, it can be tough to switch to a new format like video ads.

The bottom line is that online advertising is tough. But it's also a necessary evil if you want to be successful in today's digital world. So, if you're serious about marketing your business online, make sure to invest in a good digital marketing agency. They'll help you navigate the ever-changing landscape of online advertising and make sure that your campaigns are successful.