UX - User Experience is the field of design enlighting and useable software.
UCD - User Centered Design is a process of how to achieve this.
So, UX can't be about hygiene factors by definition, because it is no process like agile, waterfall or UCD is. It's not about how to reach your goal, it's an area where you work.
User Centered Design
You said there is no invention in UCD as it's only looking for the current needs of users. And you are right. UCD done correct is only about the moment.
User-centered design can be characterized as a multi-stage problem solving process that not only requires designers to analyses and foresee how users are likely to use a product, ...
Source: Wikipedia
Where the foresee is bound to the product, which is already there or in development. If one uses UCD for a new product, usually there is an extensive User Research project upfront in order to extract user needs for the requirements. Requirements are the base of UCD, because all design decisions can be traced back to a specific user need. This is a very engineers' driven approach of working.
The image below shows all steps involved in iterative UCD until the product is fine for shipment.
Source: UXPA
Design Thinking
There is a quite similar technique called Design Thinking (made popular by IDEO) and it has its emphasis on invention and ideation. Actually it puts more effort in brainstorming, thinking outside the box, design even if it's ridiculous at first glance...
The design thinking process is best thought of as a system of overlapping spaces rather than a sequence of orderly steps. There are three spaces to keep in mind: inspiration, ideation, and implementation. Inspiration is the problem or opportunity that motivates the search for solutions. Ideation is the process of generating, developing, and testing ideas. Implementation is the path that leads from the project stage into people’s lives.
Source: IDEO
And you can see at image below, there is a step more called Brainstorm. That is probably the main difference ;) No, but the attitude of it. You are actively looking for innovative solutions rather than fulfillment of needs only. User needs aren't documented in detail and keep somehow diffuse in the experts brain, because it is a document-light process. For more other techniques but brainstorming see here.
Edit: One of the main differences to UCD is the extreme cooperative and interdisciplinary approach of Design Thinking. Here everyone can design solutions. UCD is driven by experts and others are taken for "data" input only.
Source: University of St.Gallen
More to read about Design Thinking: IDEO, University of St.Gallen, Interview at Fast Company and a quite comprehensive collection of papers at Sydney Design thinking Research Conference
Edit: Added LeanUx
Lean UX
LeanUx comes from the need of startups to quickly bring products on market without a big budget. It's the lightest process of the three.
Lean UX is the practice of bringing the true nature of our work to light faster, with less emphasis on deliverables and greater focus on the actual experience being designed.
[...]
The team begins to provide their insights on the direction of the design as well as its feasibility. Changes are then made to the original idea, or perhaps it’s scrapped entirely and a new idea proposed. The initial investment in sketching is so minimal that there is no significant cost to completely rethinking the direction. Once a direction is agreed upon internally, a rough prototype helps to validate the idea with customers. That learning helps to refine the idea, and the cycle repeats.
Lean Startups mostly iterate their (working and sold) product from basic features to more advanced in order to earn money early (it's called minimal viable product MVP). An Agile touch gets LeanUx from its deliverable avoiding process. Ideally your prototype is coded in your target technology, so the prototype transforms smoothly into your product. In the image below you see the Leanux process.
Source: Smashing Magazine - LeanUX
The biggest difference to the above shown methologies is the lack of a research upfront. You do your concept in a dust and validate it internally first. The usability test with external users is the first contact of your idea/concept with reality. It's obvious, there is no research, no need finding, but a solution offering. That's startup - less money, less time. And one should mention it, no big risk of a failure, because solid companies can't risk a fail that easily. LeanUx is meant to be used in design phase only, so it can be used with Agile and even Waterfall easily.
More to read about LeanUx: Smashing Magazine - LeanUX and Jeff Gothelf about LeanUx
Edit2: Added Data Driven Design
Data Driven Design
Data (or Metrics) Driven Design is widely adopted by big online plattforms' or software vendors in order to optimize their product - namely conversion rate.
Every design choice is tested
Takes others experience with a grain of salt
Design is a logic problem
Rely on data for decision-making
Aesthetics are secondary
No detail is too small to test
Never trust your gut
Cold, calculating
Source: Joshoa Porter, Slideshare p10
Reading the sentences show an approach of objective and analytics-based decision making process. There aren't human experience, gut instinct nor arbitrary decisions, but pure experimental setups to see what works best. Even there isn't an idea, why it works best, it's just do it. Data Driven Design has its best benefits in optimizing software. Nothing is too small or minor to be optimized and wording can be optimized as well. With huge differences as an experiment of Dustin Curtis has shown. His goal was to improve the Click-through-rate of his twitter link and "minor" changes in several steps from "I'm on twitter" to "You should follow me on twitter here" increased the performance from 4.7% to 12.81%
Metrics-Driven Design Framework
1. Identify Business Objectives
Make sure the design team is aligned with the executive team
2. Map out your UX Lifecycle
What specific actions do people need to do in order for you to meet your business objectives?
3. Identify your Core Metrics
Metrics fall out of the UX lifecycle. Focus on the biggest and emergent hurdles over time.
4. Continuous Improvement Lifestyle
Changing the way we think about metrics and design will become crucial going forward.
In DDD all impact is measured by metrics. So, it's essential to define your core metrics first and use them to always control your product. Your goal is to optimize rather than to innovate. But this works well and precise even into smallest details. You ask "What works best in the current model?" rather than "What is the best possible model?". Therefore this process isn't suitable for innovation, but in testing a new and innovative product in comparison to the older, established one (AB testing). So, it can be combined with the former processes and be used for setting up a benchmark system. Data Driven Design has its benefits for clear communication of business values/sales/conversions in a language management is used to and understands.
More to read about Data Driven Design: Slideshare1, Slideshare2
Summary
So, one could say UCD is more an engineer attitude - problem found, problem solved. And in an engineers' attitude, all decision are traceable back to a requirement.
And Design Thinking is a designers' attitude - problem seen, play around, solution found. The ideation phase isn't really traceable, so the solution is a bit arbitrary.
LeanUx is out of a startup-mind - solution proposed, solution tested, solution refined. The emphasis lies on a fast product launch and gradual advancements.
Finally, Data Driven Design comes from a marketing perspective - set up business goal, test refinements, take best measured. It is not aiming for innovation, but optimization.
