It is comfortable to know how utterly robust the recovery process on Hive is. The algorithms governing the security of your account and its recovery - should anything go badly wrong - work, and they work very well. As long as there are a few critical settings in place, you can feel secure that your account will always remain under your control and, even if you get hacked or your keys are stolen, you can fairly easily get it back.

Here's what to put in place to secure your Hive account:

ensure your 'Recovery Account' is set to something other than 'steem'. This could be an alt, or somebody you know and trust. If you were on the Steem blockchain before the birth of Hive and you haven't changed the recovery account, there is a good chance it could still be set to 'steem'
ensure your 'Master' and 'Owner' passwords are always stored offline in hard and soft copies (printed and on some form of removable media). These are almost never required and they do not need to be handy. The only use case I know of for the 'Owner' key is to change the keys of the account or to recover it. The 'Master' password is the key generator by which you can obtain all the keys for the account. Keeping these two bits of valuable information offline will ensure that nobody can steal them from your computer and also that you will not use or lose them by mistake. If you do reveal your posting or active keys or you get hacked, your owner key will allow you to immediately change the account keys and stop any actions that may have been taken on your account. If a hacker obtains your owner keys, then, by changing the account keys, you may be locked out altogether - not your keys, not your account/crypto. HOWEVER, even then you have a chance at recovery - how amazing is that? As long as you have a functional recovery account (ie not set to 'steem', but someone you trust or an alt), you can use an 'Owner' key which was valid no more than 30 days before the recovery attempt, in order to immediately recover your account and regain access with new keys that supersede those of the hacker! This is incredibly robust.

Summary of Hive account keys:

Posting: the key used most often (posting, commenting etc), but without the power to make major account changes
Active: the highest level of key you will ever need for practical day to day transactions, such as moving funds around or editing your profile
Memo: a low-level key used for reading encrypted memos
Owner: this is the highest level of key for your account. AFAIK, you would only need this for changing account keys or account recovery; it is best stored offline in hard and soft copies and not on your phone/computer
Master: this is the 'key generator' for the account. Even if this is the only key you have, it can be used to generate the correct keys for the account using a tool like Hiveworld or PeakD; this Master Password is best stored offline in hard and soft copies and not on your phone/computer.

Why is this post being written?

Simple, I went through the month of October in a coma of lost account and keys due to not having observed the critical points mentioned above. I wasn't hacked, but I did lose access and I had thought my account was gone for good. For all but a heart-stopping 9-minute window out of 30 days, the recovery account was set to 'steem' and I could do nothing about it.

I ended up studying the recovery process from multiple angles before eventually arriving at a way of recovering the account, helped enormously by Hive witness @deathwing. It was a breath-taking adventure which you can read about here, and one I would not wish on any Hiver. I am sharing what I feel to be the gems of this experience - fortunately not a bitter one - with anyone who might not be aware of how badly things could get messed up and also how easily such a situation could be avoided entirely!

Resources:

Hive Account Security: Take These Two Steps And Never Ever Lose Access

Here's what to put in place to secure your Hive account:

Summary of Hive account keys:

Why is this post being written?