Do you know why vaccines take so long to get to market?

1) Money. It's expensive not only to generate the basic data needed to show a vaccine is possibly effective, but to run large clinical trials and get approval to run these trials. Not an issue for the SARS-CoV2 vaccines

2) Patient recruitment. It's hard to get people to consent to clinical trials. People aren't clamoring to get the new meningococcal Y vaccine and you need large groups of people to show efficacy. Also not an issue during a pandemic where people want to get the vaccine ASAP.

3) Exposure. Let's stick with meningococcal vaccines. There were ~300 cases in the US last year. If I vaccinate a random 100,000 people, there will statistically be 0.1 cases in that group. Though this isn't the perfect comparison, the Pfizer COVID vaccine trial had ~200 people become infected. While this isn't the number needed to show efficacy, if I was to preform a meningococcal vaccine trial that needed 200 cases, I would need to vaccinate ~200,000,000 people total. Typically you would do this trial in a region with lots of meningococcal cases not America for reasons I outlined above. That is logistically difficult but doable. There are many cases of covid in every country at high enough numbers where you can run the trial pretty much where ever and see enough cases to show efficacy.

4) Regulations. Typically you have to show data sequentially and get approval between each step of the process. The approval process takes a long time, typically because many drugs are looking to be approved (basically there's a long line). Because of the urgency of this vaccine, some steps were run in parallel and approval between steps was given top priority.

There were no steps skipped. The science is solid. The speed at which the vaccines were created is not an indication of their riskiness, but of the monumental achievement of the scientists behind them.