To really get a grip on the "worst" part of being a biologist, you would need to get feedback from many, perhaps dozens, of professionals in the field. Biology is an extremely broad career topic. There are all sorts of folks, personalities, interests, philosophies and so forth. With some sort of degree in biology you may find employment quite easy if you are flexible. Some people are not flexible. I knew some who were determined to spend their lives researching white-tailed deer but there are very few jobs limited to white-tailed deer. I remember one such individual who ended up, instead, studying fleas on deer and he became an entomologist. Being flexible helped him. Others often complain they become more chemists than biologists. Indeed a degree in biology does often qualify you to do chemistry work and you may very well find employment with chemistry such as environmental testing and medical testing. But you need to be willing to make that switch.
I see the hashtag for marine biology here. I started with an interest in marine biology and I took several marine biology courses in a consortium (a long time ago), but you have to be realistic. It is still work and it can be exasperating. In other words, it is not just swimming around petting whales on the head. Some find it quite different from what they imagined. Indeed some marine biologists I knew spent only a week or two on the beach collecting samples and then spent the rest of the year examining their samples at home sitting in a lab!
Although biologists are usually employable (if you are flexible) often the pay is not as high as, for example, folks with an outright chemistry degree. Some find this a problem and may end up. as my sister did, changing careers entirely. She worked in a drug testing lab for several years and decided she could not afford to raise her daughter for the limited income. However, this is not always the case! If you were, for example, a marine biologist working for an oil company, you could find yourself in a very good way. You just have to be willing to work for an oil company! I used to work for a very large pesticide company and decided I was not suited for that environment.
Another issue, you are likely to find you must get a graduate degree. A BS is good but an MS or PhD will much more likely open doors for you. Some are not prepared to take on additional schooling after undergraduate. This point may also lead to some major geographical shifts for you! Some do wish to stay within a certain radius of home or some other favored geographical area. Opportunties from much further afield may create new plans for you if you are willing.
I could say much more but I hope this gives you some idea how personal and complex your question is!
Molecular biologist here! I had to move to Boston MA for work since this is where one of, if not the largest, biotech hubs is. I work in research with RNA interference as a mechanism for therapeutics but I have also worked in Next Generation Sequencing labs, in a fermentation lab (pharmaceutical active ingredients derived from biologics), and in a tissue engineering lab. I chose to go back for a master's degree after a couple of years working but didn't want to commit to a PhD. I think that's a pretty personal choice but really comes down to what sort of position you want to have and what work environment you want (example: lab-based vs bigger-picture/project-creation and academia vs industry).
The lab work is my favorite! It's a point of pride to run an experiment well/consistently and to be able to tell a story about a certain biologic process that helps lead to treatments for disease or publications.
The tough part is when experiments don't work as you expect them to or when you're trying to sort through an overwhelming (or underwhelming) amount of literature to inform the pathways/genes you're interested in. You also have to be able to take a failed experiment and analyze that for what it is without taking it personally - I've known a couple of scientists who couldn't handle that and led to fabricated data (the worst possible outcome!). Another tough part is that some experiments are very involved and when you start, there isn't always a convenient stopping point. So you might spend 10 hours on an experiment simply because of the logistics/incubations/preparation. When the long experiments fail, it can be pretty disheartening.
But I love the work and I am paid really well with a Master's degree. If you don't mind moving to Boston, the Research Triangle in NC, or San Francisco/San Diego then you will likely find a ton of work options in industry! Of course there are other options in biology but these places are your best shot at something really interesting outside of academia.
Best of luck!