Unfortunately, that's the outcome of complete decentralisation. As soon as the decentralied system becomes too large, mistakes and misunderstanding between nodes arise. In blockchain system it leads to forking (hard forks or soft forks)... Also, internet connection is a specific problem: miners do have high data processing speed, while connections between nodes don't. This also leads to information exchange problems, which eventually lead to strong need of centralisation, which opposes the whole concept of blockchain system. A loop is then repeated...
You should read the previous comments, specifically by @BlackHatCoiner. This had nothing to do with internet connection, data processing, orphan blocks, "misunderstanding between nodes", etc. This was simply an invalid block created a miner.
The reason for things like this happening stems from incompetence developers who do not have a deep understanding of the Bitcoin protocol and its details such as the one leading to this mistake in the customized code the miner was using to create the block they mined.
We see incompetence like this from time to time too. For example a while ago we saw blocks that had too big an OP count that surpassed the allowed number and made the block invalid. Another detail that the developer who wrote the code for that miner didn't know!